I love running but I’d definitely warn anybody thinking about selling their bikes to keep it in the shed instead, if possible.
I was running a load of half marathons fairly recently and a bit of trail running and honestly thought I wouldn’t bother cycling again. But I’ve come full 180 degrees now and loving mtbing at the minute and can’t be arsed running at all other than forcing myself to do the odd 10k after work.
Plus running takes a heavy toll on your body- you’ll really appreciate having the bike when you can’t run due to an injury. Plus when you ramp up the training for an event or whatever it’s invaluable to be able to spread the load and do a bit of cross training. Or it was for me, anyway.
I definitely know what people mean about ‘no faff’ though, all the gear and kit for mtbing seems ludicrous after you’ve been away for a while.