A lot of software is built and optimized for x86 and EPYC processors are really good so it is hard to get into arm, don’t think that many companies use it.
I don’t think a lot of companies realize they are using it. At three companies now, I’ve witnessed core microservices migrate to ARM seamlessly, due to engineering being direct pressure to “reduce cloud spend”. The terrifying (and amazing) bit is that moving to ARM was enough to get finance off engineering’s back in all cases.