Oh I can see a Di2 rear mech loving the lakes boulders & constantly wet trails in winter, imagine how you’ll feel rocks clattering of the mech, Ohhh my mech fannying about worrying just like when you batter Enve wheels thinking oh have I damaged it…. never mind the cost of replacing it if you rip the mech of with a big rock strike.
It may well have a place with the elite race whippets to save a few seconds here & there but not hard core big mountains, imagine popping into your LBS & asking for a new Di2 mech of the shelf, not many bike shops will stock it due to costs.
Don’t get me wrong I’m all for technology but what’s wrong with 1×11, the biking general public are just settling into new bikes designed around 1×11 & now electric shifting is the new buzz word on the street, Ok for roads until it’s really proven then see how it fares with mud crud & the great British winter & a bit of neglect.