As one of the folks that was present during the early decision-making around this, this was a wart that I wish the team had heeded me on fixing early on. Once they introduced "classically confined" snaps (that is, snaps that have no confinement and exposed the real filesystem hierarchy to them), there was no fixing this anymore. To be clear, the decision to stick to their guns on /snap predates the introduction of "classically confined" snaps.
The reason that "classically confined" snaps don't work on Fedora out of the box and don't work on Fedora Silverblue at all is because of this wart. Fedora's snapd uses an alternate path because /snap is not allowed. This means that /snap path doesn't exist, but it also means that "normal" snaps work fine on all Fedora variants, since it doesn't require an FHS hierarchy mutation.