@dumpsterqueer Back when I first implemented mastoapi support, many (masto) clients used the (masto) version to determine feature compatibility iirc.
It's a different story now as masto/pixelfed/pleroma have diverged wrt endpoints and entities to the point that clients can't trust the version field.
It's quite the pickle, either we continually update our endpoints/entities to remain compatible with masto clients or risk them becoming incompatible.