This happened because of changes in Linux 5.18 to RNG’s crypto and backports to older LTS Kernels. Basically the entropy_avail number is now meaningless. But I don’t have any real inside in how it’s now working.
The changes can be found here.
https://kernelnewbies.org/Linux_5.18#Security
If you search with “linux 5.18 entropy_avail” you might find more information on the internet.