This seems like a pretty rational opinion to me. Thread title is a bit hyperbolic and obviously going to rankle many fans. I think both sides have got points underneath the ladlefuls of passive aggression. You can't really ignore goals and assists - it's a key stat and no coincidence the most productive players in this regard are the most valuable players in world football. But you can't ignore all the other aspects of the game at the same time. I wonder what Mahrez' numbers would be like if every time he got the ball his sole focus was on scoring and assisting, to the point he would lose the ball many times because of taking on that risk. Over the season his individual numbers would likely be a lot higher, but would Man City be a better team? I would argue no.
This is the crux of it for me with Rashford. He is like a ship cannon that on a good day might blow up enemy ships that all the other cannons cant. However the cannon is temperamental and occasionally backfires into its' own ship. It falls on management both for club and country to manage the situation. For all his faults Mourinho did recognise that getting the best out of Rashford (and Martial) was having them compete for places. Rashford's place in the team has come too easily and I think the stats and his ability to do something amazing do bely the fact that he is often pretty costly to Utd and England during attacking phases, as his concentration on being directly involved in a goal often sees him choosing really low percentage options like beating 4/5 players or other trickery (which occasionally comes off and he looks world class, but often doesn't and results in the team busting a lung trying to get the ball back). He's got fantastic ability but if he's injured he should be rested and if he is losing the ball too much he should be benched and have a serious competitor for his place in whichever team.
Also an argument that the fact it's so divisive is what's 'toxic' rather than people being staunchly in one camp or another. Regardless of who's 'right' the fact it causes so much fireworks probably isn't positive for whichever team. The simplest solution would be Rashford is managed to become more team orientated. If ever there was a player needed a coach like Guardiola it's Rashford. I think he probably would become world class in that setup. As it is, this situation will likely to continue. On occasion he'll be an amazing match winner and on countless other occasions often the weak link in the possession chain. The fans on one side will point to his occasional great performances and stats and the fans on the other side will point out the flaws that make the team weaker. A lot of people will argue with each other and get upset and meanwhile we probably won't win anything.
I think it ties in to the cult of celebrity we have in this country with our football players and this is maybe what the 'cult' aspect is that the OP is getting at, bit of an antagonistic word choice mind. The public seem to need a big hotshot 'roy of the rovers' type player who is the star man and Rashford - because of his moments of brilliance - gets this status. We used to have it with Stevie Me, who was obviously pretty good, but so devastatingly poor in international tournaments due to this expectation on him to do something like an Olympiacos volley and win.a game in the dying minutes. This culture does get so boring after a while as anyone with half a brain can see that we need a team that is a well oiled, well drilled machine that is pre-prepared for every situation and that when component of that team 'isn't working' it gets replaced with one that is. That is why after this season, I think it would be criminal for Rashford to be started in England's XI when we have so many players who are on current form equally dangerous but have also proven themselves to be much more effective as components in a team.