Yeah, it is very relevant.
Question - Would Democrats rather have four years of Trump and then he loses in 2020, or two years of Trump and six years of Pence?
Because if Trump's favorability numbers are actually in the 30s, he has a big chance of losing in 2020. Especially with a motivated Democrat base.
Pence is much more likable than Trump, far better spoken, and doesn't shoot off with his mouth or on twitter. His favorability numbers would be much higher than Trump's going into 2020.
Those who want Trump gone now, therefore want Pence in, are too short-sighted to think about the long-game of their political decisions.