Atleast in my parts, Conrad is a big sponsor of Maker stuff (they profit of the parts, after all, especially makers that don't want to handle customs), so they're fine in my book. From what I know from german makers on youtube and IRL, the fair is pretty decent and well staffed with actual makers.
I can confirm. It has definitely gotten more commercial over the years, and I also wish they would get rid of some stuff that plain weirds me out (don't get me started on the BattleBot arena... also, some of the cosplayers...), but as I said: all in all, it's still OK.
One thing that has historically put me off about the maker community is these artificial distinctions where materials and ways of making things that have historically been considered "girl stuff" get less respect, or sometimes don't even get recognized as making at all.
If you use such a definition, a cosplayer who makes their own props and sews their own costumes qualifies for sure.
Some costumes require custom mechanical props. Spiderman's eyes in recent movies have the mechanical-quirk. So reproducing that mechanism in real-life is certainly a Cosplay + Maker thing.
There's a lot of Cosplayers using LED Lights for highly color-accurate "glowing" effects (common for high-end Overwatch Cosplayers). Some cosplayers are just sewing / stiching things (which is fine: that's still a skill), but there are other cosplayers who are putting serious effort into their electronic components of their costumes.