In my experience gmail has the best features for day to day business email management. Sorting, taging, automating, autoresponding, synchronizing across multiple devices…
It doesn't sound like OP was talking about a business email account, does it? Even so, all the stuff you are saying is better in gmails web client (?) I can do in thunderbird.
Yes but only locally on a single device.
Why, you never heard of IMAP?
I know imap but it only helps with synchronization… the tagging, sorting, automating, autoresponding all only works locally on your device. If your device is shut down, nothing will happen to incoming mails. Gmail does all these operations 24/7
Ok, I guess you're right about that stuff (until thunderbird sync is released), but I'm not convinced using gmails web client is the answer. I think most email web clients will give you this solution, no? And if not, then there's nothing to complain about because you've selected your tradeoffs.
I tried a lot a few years ago. Gmail was the best fit for my needs. Gmail originated as a side project from a google dev. He invented it because he himself needed the features because no other app provided them. Maybe there are better solutions these days?