1-5% of traffic that comes from people using devices that are at least 4 years old. Someone who can't or won't upgrade from a phone that still uses Android Marshmallow is probably not bringing in much revenue.

Exactly. The “easy choice” is to drop support for those users. I suspect most web developers won’t even notice.

It’s a pity - there’s no essential reason why old phones with new batteries should get worse over time. But software kills them in so many ways.

As long as this statement is true. They also dont's say who these big integrators are and the situation may be widely different between integrators and fields.