Really? Mine is the exact opposite experience. Gmail, the website, takes at least 2 minutes to load and be usable, so much that I need to use a separate extension to use it normally (Checker Plus for Gmail).
I'll mention this yet again so everyone can ignore it, but if you use the HTML-only option, it's clunkier but very fast. But I can say this 100 times and nobody does it.
Something is pathologically broken for you. Don’t know whether it’s client side like a corrupted browser or service side like a malformed attachment that is causing Gmail to thrash. Chances of course are that the problem is on your end.
100% sure. I have been using gmail since forever on all sorts of networks and devices and never ever has taking "being useful" 20 seconds, unless there is something very wrong on my side.
Weirdest thing is that an add-on makes it faster, how's that even possible without a serious MiTB problem?