I'm willing to throw everything out as long as it is very infrequent, for a good reason, and known to be for a long lifespan before doing it again.
Going from 30-pin to Lightning was acceptable, as it really does seem to be a 10+ year future standard, and Dock had been around for a long time (although it is a real pain for the car; I'd like to put in a lightning spec dock, but I need to find audi radio keys and either do it or find someone else to do it who won't screw up my electrical system this time (sigh) and really I just hope my car gets totaled and a Model S falls from the sky.) Going from MagSafe to MagSafe 2 was infrequent, but didn't feel meaningful.
I got pissed when ThinkPads moved from 14.4V to 20V sometime around the T43p -> T60 series, which is when I moved to Apple, so there's always a risk.