Its viewed as a really difficult league to play in but for all the wrong reasons.
Physical. Horrible travel. Coaches that favor north americans.
Its not where you go to develop with a few exceptions (like the Leafs, Lightning or Pens system.)
Nothing to do with national pride. Unless you mean the AHL coaches preferring north american players.
1) It's a league with a substantially higher level of play than the non-KHL Euro leagues and serves to bridge the gap and be a stepping stone.
2) Damn right it's more physical. And Euro players have to adapt to the increased level of NA physicality and a smaller rink.
3) AHL teams usually play the same system as their NHL parent club and so it serves to help that adjustment as well.
If you want to play in the NHL, you'd better be prepared to play in the NHL as part of that process. And if you aren't, you're going to fail unless you're a marquee talent.
If Will Lockwood or Aiden McDonough told the Canucks that they were either playing in the NHL or bolting to Switzerland when they finished their NCAA careers ... they would have no chance at an NHL career. If Juho Lammikko didn't spend that time in the AHL, he wouldn't be in the NHL right now.
Like, if you want to play in the NHL, you'd better be willing to take the steps required. If you think you can just wander in from a miles worse Euro league with no adjustment to NA rinks/systems/play ... it probably isn't going to work out for you.
And absolutely running down the AHL is a national pride thing.