Yes, we’d never been there in our history isn’t that enough reason to want to give ourselves the best chance by playing our best, fit, team rather than catering to the whims of players. What now if we get to a Final and Lloris isn’t fit, do we select him as we shouldn’t let him down?
Always pick the team that provides best chance to win. If Kane is a team player, then he would rather we were successful and he was rested, than for him to play simply because he’s our highest profile player.
I think Kane was selected as he was the most likely to score a chance as he is our best finisher. I think the hope was that if it was a game of few chances then Kane could take one of those and be the difference maker.
Of course, pochettino also could see how Kane was in training so perhaps he felt that Kane was ready anyway.