Agreed, it is unfortunate that they believe there is no longer enough benefit to open source their newer computers. But I'm interested in why that takes the OSTC off the table for you? As far as I know the Shearwater lineup isn't open source either. Happy to be corrected on that.
I really don't buy the argument that buying an OC/CC capable computer will be the last one you ever need. If I ever go down the CC path, a new computer is going to be only a small expense compared to the rest of the required investment,
I want my primary computer to be trimix-capable (I don't dive CCR yet, but I do dive OC with trimix), have a good screen, Buhlmann w/GF, and have AI. When the Perdix AI came out, it was the first computer on the market that had everything I want, so I bought it. Prior to that, the OSTC 4 was on the table because I had understood it to be open source and the ability to modify the code of the computer has some appeal to me. At the same time I was considering the OSTC, Shearwater did not have an AI computer, so they were both on the table if I decided to buy another computer. If they updated the OSTC 4 to also have AI, and it used the same transmitters as Shearwater, Oceanic, AquaLung, etc. are using, it would be back in contention. If they commit to releasing the OSTC 4 code, and keeping the public code up to date, it would be back on the table. If my SeaBear H3 (now, my backup computer) were to die, I would consider the OSTC 4 as a replacement (if it was open source). As things stand now, if my H3 died, I would replace it with a second Perdix AI.
As long as the OSTC is not open source, the hassle of buying it from Europe, the unknown of how responsive customer service would be if I never needed service, and the fact that they don't even fully support Imperial units on the OSTC 4 (and don't seem bothered by that) are all reasons why it is not on the table for me any more. Not as long as Shearwater keeps up with their top notch computers and customer service.
As for going CCR, I fully expect that my Perdix AI would carry right over to use with a CCR. One of my main dive buddies dives a JJ and has been using a Perdix as his backup, but is now upgrading to a Perdix AI so that he can also use it for single tank recreational diving on those kinds of vacations. A CCR will probably run as much as $10K, but even so, a $1K computer is not chump change, and a Perdix AI very well COULD be the last one I ever need.