Those are all totally fair considerations, just not requirements in my workflow. I’m coming at it from a personal use case, where I don’t need offline access to my personal email, and I only have one email account to check (my Gmail is forwarded to my Proton mail).
My question was more to lead OP down the requirements gathering path, to evaluate their actual needs and if a client is actually required or if it’s more of a “nice to have”.
Thanks for laying out some of those advantages to a client though. Every user has their own needs and if offline access, multiple accounts, consistent UI, etc. are desired, then a client is certainly a great option.