(written from a Production point of view)
4K Ultra H(igh)D(efinition) Blu-ray, or 4K UHD (BD), is a Blu-ray Disc format offering 4K HD 2160p resolution digital video and slated to become the successor of the 1080p resolution Blu-ray home video entertainment format. Star Trek and Star Trek Into Darkness were released in 4K UHD on 14 June 2016,  five months after the home video disc format proper was introduced to the public. Star Trek Beyond was released in 4K UHD on 1 November 2016.  The quick release on the format was due to the fact that these films – the first ones for Star Trek to be entirely produced digitally – were already shot at the high resolution standards required for their respective large screen theatrical releases. (see also: Remaster)
A 4K UHD BD release of Star Trek II: The Wrath of Khan (Director's Cut) was planned, made possible as the film had already been remastered in 4K UHD resolution for the occasion of the film's 35th anniversary, which resulted in the 2016 Star Trek II: The Wrath of Khan (Director's Cut) Blu-ray disc release – though it had to be downscaled to the 1080p resolution format for the underlying Blu-ray release. 
Despite being marketed as such on some retailer sites, such as Amazon.com, the 4K UHD BD format no longer employs the geo-restricting region format of its Blu-ray predecessor, becoming the first home video format to acknowledge the ultimate irrelevance of geo-restriction after its introduction by the DVD format in the early 1990s. 
While the DVD had been a commercial break-out success from the moment it became widely available, its intended successor Blu-ray suffered from a much slower consumer acceptance for a wide variety of reasons (see main article). And it is indeed almost the exact same variety of reasons – the replacement, and digital alternatives issues in particular – which had led to the even slower adoption of the 4K UHD disc format. As of 2019, the intended Blu-ray disc successor is still only appealing to the relatively small niche market of affluent "film buffs". This is to a point substantiated by the professional industry site The Number, which has reported a combined US domestic sale of US$331.2 million for all physical home video formats of the three alternate reality films as of June 2020 (excepting the hereafter metioned 2019 release for which no figures were available yet at the time). However these figures encompass all three disc formats, and it is save to assume, given the substantial retail price differential between 4K UHD BD and its two predecessing formats, that the former only accounts for a small part of it.  Replacement issues are playing an even greater role in the case of 4K UHD as accelerated advancements in display technology has already resulted in the commercial introduction of the very first 8K UHD 4320p resolution (the indended successor of 4K UHD and starting to approximate something akin to pseudo-3D) television sets in late 2019, a mere six years after the 4K UHD format consumer market introduction and long before it has even reached a modicum of its full market potential – even television transmissions in 4K UHD were still virtually non-existent as of 2021. The early advent of 8K UHD has the real potential of making less afluent consumers decide to skip the 4K UHD phase altogether in order to avoid what they call the "double-dipping" phenomenon.
It has become the primary reason why the in 2016 announced 4K UHD disc version of The Wrath of Khan (Director's Cut) has not seen the day of light yet (it has seen a very limited September 2017 theatrical release though ), even though the remastering work to 4K UHD standards for that film has long since been completed, and why no other 4K UHD projects for any of the other older Star Trek titles have even been considered to date, when discounting the 2019 Star Trek Trilogy: The Kelvin Timeline 4K UHD release, which was essentially a mere reissue of the 2016 individual releases of the three alternate reality films. Having been the only Star Trek release in three years time, it is in itself indicative of the slow consumer adoption of the 4K UHD disc format. Nonetheless, both Trekcore and TrekMovie.com have in July 2019 reported that preliminary talks were resumed for a remastered 4K UHD release of Star Trek: The Motion Picture (The Director's Edition).
Nonetheless, the potential of 4K UHD as a physical disc format becoming economically viable in the long run remains to some extent, as producers of both HD television sets and HD playback machines increasingly incorporate the 4K UHD display option into their newer (affordable) models – provided that the pace of display technology is slowed down somewhat by delaying the introduction of commercially available 8K UHD content of which there is none as of 2021. That being said however, the home video format industry (as in, the physical discs producers and distributors) is very much impotent to counteract the rapid growth in popularity of the digital alternatives, the HD video-on-demand (VoD) streaming services in particular as provided by, for example, Netflix, Prime Video or CBS All Access, each of them in various stages of preparation of streaming in 4K UHD as well. Ironically, the introduction of the 4K UHD BD in February 2016 was actually promoted by the industry as a means to combat the streaming media,  which only served to prompt these same streaming companies to start preparing for the advent of 4K UHD themselves, Vimeo having been the first one to do so, already in December 2014. 
|Home video formats|
|Super 8 • Betamax • VHS • CED • LaserDisc • VHD • Video 8 • VCD • DVD • UMD • HD DVD • Blu-ray • 4K Ultra HD • Digital|
|14 June||Star Trek, Star Trek Into Darkness|
|1 November||Star Trek Beyond|
|15 July||Star Trek Trilogy: The Kelvin Timeline|
|Unknown||Star Trek II: The Wrath of Khan (Director's Cut)|