I packaged an app (newsflash) as a snap and it requires more memory than the default 2G. I currently solve this by manually adding the flag to snapcraft command. It’d be better to pass these parameters via snapcraft.yml in order to avoid documentation etc.
Nevertheless it could be useful to have in all cases. For example, LXD containers (or --destructive-mode) might not be constrained in resource usage, but it could be VERY useful if they could warn you about exceeding stated (or assumed) memory requirements.