Apologies in advance to those who don't want to read positive things about Benitez, but I was asked!
The main reason he was so loved is that he was the opposite to Mike Ashley. He was ambitious, dedicated and dignified; he engaged with fans and communities off the pitch, bought into the culture of the club and strived for betterment: he was the embodiment of everything Ashley wasn't. A reflection of what we wanted our club to be, whilst simultaneously representing the polar opposite to the sneering incompetence of his employer. Plus he stayed with us despite not having enough in the tank to keep us up that season; a failure that wasn't on him (he had ten games; we went the last six unbeaten).
As for his performance; he did well. To start, we won the league at the first time of asking - an achievement unfairly downplayed in English football, particularly when you look at how so many have remained there and/or fallen further still. Then we finished 10th in our first season back and mid-table again the year following, despite a meagre budget compared to others.
As for Eddie Howe, how long he is the manager of Newcastle is entirely down to him now. On paper, he's just what we needed after the hands-off buffoonery of Bruce; though it's clear he can't just coach us out of this mess: January reinforcements were absolutely critical. They've arrived and so if we go down now, he's failed and should lose his job imo. Keep us up and the sky's the limit, it's a huge opportunity for him and us. It would be nice if we could grow together cos I've little to no interest in us artificially purchasing titles a la similar cases.
I really like him as a person but remain unconvinced in terms of his actual management ability. He's averaging a point a game, which is enough to keep you up if you don't have a Steve Bruce handicap. But we do have that handicap, so he needs to find an edge and quickly.