I agree. I work in a large-ish company (~9k) who a few years back moved from Exchange/Outlook to GSuite (with POP and IMAP disabled) - so using anything but the Gmail web interface and/or the mobile apps is out of the question. Add in the obligatory (and yes, slightly annoying) corporate managed email signature (HTML), the fact that everyone is used to just copying images/screenshots inline with the text, and of course the very tight google mail/calendar/drive integration, and I don't think that even if I could use a text-only client outside the Google ecosystem, it would be a viable option.