Accessing His Majesty's Government services online

My goodness, all I wanted to do was set up e-mail reminders of vehicle tax, which I'd already managed to pay online. I already have my Government Gateway login details all set up, etc. But, no, I had to go through a whole other palaver involving setting up my GOV.UK One Login mobile app with a new account and photo ID and suchlike, before I could set up those reminders.

I'll give it to them that at least they don't change the system every year but a smoother migration to whatever the critical new functionality is than just set up an entirely new account would be appreciated.

(Of course, I have a separate login for the Scottish Government but that seems reasonable. Accessing any US Federal Government services is a pain without a US cellphone number.)