At least he is out riding - it's better than sat on a couch puffing the ciggys.
I've been out with a few eMTB riders - yes you get hammered on the hills, but on the flat. downhill nope. One lad mentioned he used to have an eMTB but get fed up waiting at the top of hills for his mates so sold it once he got fit enough.
If it means someone can get out, then fair enough. You (we) are lucky enough to still be fit enough to ride bikes without assistance - some folk think I'm incredible for riding 30 miles on my MTB - why, it's just something I do (just like everyone on this forum) - but to Mr/Mrs Average, 30 miles seems like an impossible achievement.
I've been passed by eMTB's at trail centres - I've been there chewing my handlebars trying really hard up a climb, no-one passing me, then I see two bikes catching really quickly. I think 'they must be very fit or....' ah.. as the whir of the motor is heard. Some folk get very upset, but I just said 'oh, give us a tow', they laughed.