I have been working on using cloud FPGAs as replacements for HSMs for this reason. They are inherently single-tenant when you use them, and if you do everythin

I have been working on using cloud FPGAs as replacements for HSMs for this reason. They are inherently single-tenant when you use them, and if you do everything right, you can have them cryptographically shred their internal state when they are reprogrammed. You don't have as many physical security promises (but you don't own Amazon's HSM anyway, so I would argue that FIPS 140-3 is not relevant from the physical security angle), but they are a lot more isolated from other users and from meddling by Amazon insiders than Amazon's Cloud HSM is. The drawback is that they are very expensive, so you have to be really paranoid to want to use them, and they are new enough and complicated enough that you have to trust us and our auditors to have done everything right.