I agree that Mesar and Beck should be ahead of Hutson but those guys being behind Hutson in this poll doesn't necessarily mean that the majority opinion on the board is Hutson > Mesar/Beck. It could just mean that there is a chunk of voters who are very high on Hutson while the Mesar/Beck voters are mostly backing Roy at the moment and will be voting for Mesar then Beck in the next polls.
It matters but Spurgeon, Krug, and Grzelcyk are all good players in the NHL right now at 5'9", Ellis, Girard, Hughes are listed at a generous 5'10", and so on. Francis Bouillion stuck around at 5'8", and even Marc Andre Bergeron carved out a role at 5'8 with no NHL tools beyond his shot. It is certainly a factor and it's why a player this skilled was available at 62, but I think listing a height cutoff to say he's a huge long-shot to make it is a stretch with how skilled and productive he was in his draft year. The difference between 5'9" and 5'8" is pretty minimal and there's been a decent cohort of 5'9ish dmen in the last little while.
In the cap era Gionta was the only good 5'7" forward for a long time (and I guess Desharnais) and then Debrincat and Caufield were both drafted within 3 years of each other. Sometimes these things just happen in waves when players with off the charts skill find a way to be productive as smaller players. I just don't find it particularly convincing that in the long run Lane Hutson will be giving up anything meaningful in his physical game to Torey Krug, Matt Grzelcyk, or Sam Girard.