I think it might happen and that they maybe will use nvidia RTX, after all toy story world for example is mostly missing realtime raytracing to make it look even closer to the movie than it already is.
But there is another thing, last year i extracted PKG file for KH 2.8 for PS4 and inside a file launcher28.psarc i have found some files refferencing windows, at first i tought it might be just debugging leftover (console games are made on PC and test builds are often run on PC) but upon seeing some xbox one files i tought there might be more to it and it seems like i was right since we now have 1.5, 2.5 and 2.8 on xbox too and i found those files referencing xbox and windows a long time before xbox version of 2.8 even released so since there are also windows files in the launcher for 2.8 maybe they plan to release PC version of all collections and KH3 on PC
Few minutes ago i just extracted files again to make sure i was remembering correctly and yes the files are there, there are multiple files with .ps4.scd, .xbone.scd and .win32.scd extensions, you can see files in attached screenshots.
Original KH1 and KH2 were made for PS2 Emotion Engine CPU which had very different arhitecture compared to PC but was then ported to PS3 which had CELL CPU (based on powerpc arhitecture if im not mistaken) and then now final ports for PS4 and XBONE are X86 arhitecture and PC processors use that same arhitecture so that makes porting collections to PC a lot easier
And for KH3 and 0.2, those are made in Unreal engine which is really good for multiplatform releases and will make job of porting the game to PC a bit easier for the devs, im not saying its as easy as just compiling PC build from the source code but a lot easier compared to if they made kh3 in some proprieatry engine made for PS4 only
I have somewhere seen screenshots of game while it was in development and it was clearly running on windows PC so tehnically PC build exists internally at square enix as a development or debug build
I certnaly hope that they release at least KH3 on pc, i would buy it immidiatley cause i would enjoy playing it with mouse and keyboard plus better graphics and on 144HZ monitor at high framerate, plus if they would implement nvidia realitme raytracing that would really be amazing
I personally think there is still hope for PC version so lets just wait and see