When I viewed erslist from my iPhone (Safari or Chrome browser) it just asked me once to agree to the terms/conditions and then came up with a message at the bottom that said, "Using erslist often? Download the mobile version". It wasn't an obtrusive pop-up (like the TapaTalk ones you get on so many internet forums - thanks to PERB for not asking us if we want to install TapaTalk!) and disappeared by itself after only a second or two, with no action required. So far neither the terms/conditions or suggestion to download a mobile version have showed up again. I wanted to see what happened if I did click on "Download the mobile version", if it's actually an app or what.
So, for me, not really that annoying - try using ultimate-guitar, that site drives me nuts on mobile, plus the app they are constantly pushing costs money. I do see the point though that probably no one wants to download some app for erslist and have that on their phone so why are they even asking
At the bottom of the page you can switch to the desktop version, maybe that would help?