2% of traffic doesn't mean that 2% of users only have access to IE6. It may limit which computing device they can use but not supporting IE6 isn't blocking millions from your site, it is blocking them from using your site on all of their devices.

Probably not true. It means blocking them from using the site because they only have 1 or 2 devices and those are running IE.

The article talks about the fact that a lot of the seniors get help with their online stuff from the libraries (which are currently closed). What is the probability that folks like these have multiple devices at home and/or they can use them?

Years ago, a lot of my bosses at work (in Tech) still used IE. Lots of our clients used government issued computers which were locked down to IE, sometimes several versions behind.

At the end of the day, it boils down to - know who the actual users are.

never mind all the accessibility rules you have to follow (keyboard navigable, alt text for screenreaders for images, minimum contrast for sight impaired, constrained color scheme for colorblind, etc). . . that greenfield SaaS app made by 5 22 year olds isn't going to cut it here.