This is one (of many) advantages of open source software. If you have access to the source, you can build it on a ridiculously wide range of hardware. I've been downright shocked over the years at some of the strange things people have run actually useful (and entertaining) open source software on. Doom runs pretty much everywhere just for one example. ;)
also, the unix dependcy graph is formidable and needs to be supported to just bootstrap.
AFAIK Loongson's ISA is some sort of superset of MIPS64. Not exactly ubiquitous but MIPS64 has been around for a while so I would expect bootstrapping to be fairly simple.
Of course, bootstrapping is not the same as, say, using the parts of the superset that help with x86 emulation to speed things up, but even QEMU has supported LoongArch since 7.1 (over a year ago.)
The custom ISA becomes a real problem if you need Windows and other closed source software on it, but China has declared it political goal to rid itself its dependency on Microsoft.
LoongBT, faster x86 and ARM binary translation, 213 instructions