Why didn't toolbox fit your needs? I found toolbox to be a very reasonable way to install development dependencies on a per project basis while not managing multiple hidden filesystems.
It would be more accurate to say that toolbx is based on Podman, but is intended to provide tight configuration with your user's outside environment.
If you want to use toolbx for more isolation you'll have to end up turn off a bunch of features and configuring it in weird ways that ultimately defeats the purpose of having toolbx in the first place....
It is a lot easier to just to cut out the middle man and use podman directly.