Is the 1% rule for MTTs still applicable in todays games?

Unfortunately it is.
My personal recommendation for the limits you are aiming for would be at least 300 buyins, better 400.

Regards,
Asaban

wow, that is a lot! do you know if this is based on a risk of ruin formula, or just general guidelines?

It's based on personal experience after >10 years of poker and several years as a private coach
Variance gets very extreme in those big field low limit tournaments. If you don't want to deposit again you should take the saver route.
If that is not a problem for you and your mindset is good enough to adjust your limits on a daily basis, you can try it with less.

Regards,
Asaban