Yeah you need a compiler, linker and OS. That's true of any security technology. CHERI may be more significant in that regard because it's a bigger rethink than just stuffing some extra metadata into the existing types, but it's not at all intractable. We, a research group, maintain CheriBSD, a "full-fat" port of FreeBSD to CHERI (Morello and CHERI-RISC-V), so to a big tech organisation it's a small investment. The cost to tech companies is not making it work, it's often much more boring business factors.
Homepage here:
https://www.cheribsd.org/
which strangely doesn’t seem to link here: https://github.com/CTSRD-CHERI/cheribsd
Not to mention the dynamic linker.