It’s also the best squad in decades, and a once in a generation opportunity to win trophies; Pochettino isn’t doing that.
The spine of the team is Lloris-Vertonghen-Dembele-Eriksen-Kane, all of whom pre-dated Pochettino; he’s inherited great players, players who Mourinho/Simeone would win titles with.
He’s failed to win the Premier League in the previous two season despite having the best team both years, and that team is now beginning to disband; coinciding with the Manc clubs’ respective revivals, the project is losing momentum and need fresh ideas to kick-start it. Otherwise, the likes of Eriksen and Kane will begin to lose faith and patience, and it’ll be back to where we were a decade ago.
Pochettino has thus far proven to be nothing more than a glorified youth coach - he’s 46 now, so no novice either. Most great coaches had already put some trophies in cabinets by that age.