U2 have pulled it off before, though. And I'm sure Edge would be fine with it, since he is capable of playing a variety of instruments. Could lead to a very cool and interesting album by letting Adam and Larry shine.
An album where edge plays little to no guitar could be interesting and shake things up.
That would be my worst nightmare The reason I fell in love with U2 was Edge's guitar style and the unorthodox sounds he could pull out from the instrument in the 90's.
I may come off as close minded (I believe it's partly due to the fact I'm a guitar player myself) but I could stand only a few experimental tunes without guitar, certainly not a whole album.
Not a U2 album.
Plus, the best way for a musician to experiment is to pick up new instrument.
I see your point and it's a good one.
The funny thing about Edge is that when you think in a U2 song there's no guitar at all, in fact there is, cause he will make it sound like a string section, a synth or he will use a fx to "mask" it and give to the instrument new context (Passengers, Zooropa and Pop are full of these tricks).
Given this, I don't think there's a necessity for him to back off from the guitar if he wants to experiment with other instruments or let the rhythm section enjoy the spotlight.
On top off head, the only U2 songs without guitar at all are October and SOI piano versions.