If we had anything on the line in the league I'd be inclined to agree with you, since however bad Ange has been we saw the absolutely colossal downturn in form we underwent after Conte was replaced by Stellini then Mason, however I think Levy is astute enough to know the best available option to him once we crash out on Thursday is to bin Ange and let Mason/Wells take control of the team til the end of the season. There are 6 league games left of the season after Frankfurt and if Ange is left in charge for them the atmosphere will be absolutely poisonous for every home fixture, we'll be raked over the coals by the media for our continued inaction over sacking him (universally everyone in the football world can see he still has his job because of the EL QF) and the "will he won't he" be sacked conversation will dominate any discourse around the club until he is gone.
Frankly I want him to stay to the end of the season purely for the fact he will mathematically go down as the worst Tottenham Hotspur manager in history by any metric you care to measure, an accolade he deserves after how much of a massive thundercunt he has been to the fans for the last 12+ months, and the sort of unwanted title that could absolutely be an albatross around his neck when it comes to finding a new club in a serious competition.