I'm sure you're already familiar, but for others, there is also AMD's SEV-SNP [0] and Intel's TDX [1] that solve similar problems. Azure has SEV-SNP VMs in preview [2] - full disclosure, I work at Microsoft and was involved in this :)
In terms of security these technologies are (mostly) strictly worse than SGX, and there hasn't been nearly enough security research done on them. Also, the physical attack vectors remain (e.g. https://arxiv.org/abs/2108.04575). A small but interesting counterexample is x86 TSC: with SGX the MSR is modifiable by ring 0, with AMD SEV-SNP it is protected from the hypervisor. The real value of these newer technologies is not increased security, but rather increased usability. (Also, small sidenote: TDX relies on SGX.)
I think the biggest contribution that cloud providers can bring to the table in the mid-term is mitigation of the physical attack vector. This would involve inserting themselves as a second root of trust in attestations (SEV has explicit support for this), which would mean that a real world attack would require collusion of multiple parties (pick 2 of Hardware vendor, Cloud provider, Software vendor).
[0] - https://www.amd.com/system/files/TechDocs/SEV-SNP-strengthen...
[1] - https://www.intel.com/content/www/us/en/developer/articles/t...
[2] - https://azure.microsoft.com/en-us/blog/azure-and-amd-enable-...