The previous best option I was aware of with Gmail was to add a pair of Yubikeys, then explicitly remove your cellphone from the account, to close the gap you m

The previous best option I was aware of with Gmail was to add a pair of Yubikeys, then explicitly remove your cellphone from the account, to close the gap you mention. Now there is https://landing.google.com/advancedprotection/ https://landing.google.com/advancedprotection/, which might be a better option -- interested to know if you've got any opinions on that scheme.