The current rxTools is more akin to Windows Millennium actually. It's an update of an engine that wasn't so bad, but it added a lot of bugs and things have improved a lot outside of that engine since. XP is actually still a very viable OS mostly being pushed out by forced arbitrary obsolescence rather than things it's literally incapable of. That would be more akin to, say, Nintendo forcing developers with various API changes to stop making O3DS games to focus only on the N3DS for example. There are slight differences and the N3DS is improved hardware, but the O3DS is capable of almost all the same stuff.
How in the heck are they going to "patch" the hardmod method? It involves physically directly accessing the actual storage chip itself. Short of redesigning the system to use a different sort of chip that can't be accessed via a SD reader, there's not much they could do. That wouldn't stop existing systems from being moddable and it would require significant changes both to hardware and software. Actually, it wouldn't stop the new ones from being moddable either, it would simply make it more costly and difficult to actually do it. In fact, specialized hardware is no longer needed for these things now that we have super cheap heavily programmable devices with the ability to connect almost directly to anything like the Arduino or Raspberry Pi.