Mailbox.org beta offers regular 2FA setup via authenticator. I’ve been using it for months and I’m yet to run into any issues.

In general, I’ve been with MBO for almost a year and I’m happy with the service. You basically get a complete replacement for the google suite which you can use via your app(s) of choice.

1.111B class .xyz domain costs some 1 EUR per year. You’re limited to <6-9 digits>.xyz format (e.g. 012345.xyz) but if that doesn’t matter for your use case then this is the cheapest solution. You can get these via Porkbun, etc.

The recommended action when your CPU can’t handle it is to switch the mode to Filter or Filter+ instead of Dynamic. It’s not as good looking but it does darken the website at least.