I think it'd be worse if he was a stickler for something that doesn't matter all that much for forwards. Yes, it's a plus when a guy has a fast, clean, powerful stride, and it can be an issue if footwork and mechanics are the problem. But when the issue is simply that a forward's stride is atypical or unconventional, there's often not even all that much to correct.
Oshie skates like Happy Gilmore, but he literally made an asset of it. You can see it all over his penalty shots, the cagey way he moves gives him an unpredictable looseness to his approach, then he tightens it up in a nanosecond in his release and the puck is behind you. Unconventional works for him.
That's not Parascak specifically, but his stride doesn't seem to compromise his acceleration by much, and that's the only concern with his particular issue. It stands out more because his top speed isn't elite, so the uninformed "experts" talk about it like it's what makes him slower. Cleaning up his stride won't make him faster, and his edgework and control at his top speed are fine.
He can clean it up some and it might make him a bit quicker, but it's not a major concern either way.
When it's a defenseman, yes, skating matters big time. They have to do it backwards while reacting in time to speedy forwards, so good fundamental skating is pretty crucial. And when you have a D that's deficient that way, there's like 9 things you have to fix and it might be impossible. With forwards it's like 2 or 3 important things and the rest just amount to quirks you can work around if need be. We could sit here all day and name fantastic forwards that were sloppy skaters.