I'm not a collector and most guys that use their Glocks aren't interested in putting them in the safe unfired for some collector value 50 years later. A Gen 1 vs. Gen 5 as a shooter is no contest, the Gen 5 wins by a good bit.
I had a Gen 1 years ago. IIRC is was pretty well "broken in" and I think I got about $300 for it when I sold it. I didn't think a Glock 17 would ever make "Collector" status.
People collect all sorts of stuff. The real Kool-Aid drinkers are rabid for the drastic plastic Gaston gun. Most people see them as tools and use them accordingly.
Mine was a well used tool. Still functioned fine but was fugly as he11. A buddy asked if I ever cleaned it. Nah!! Maybe once or twice. It was a POS. Hate to insult or step on toes, but I am not a fan of Glocks at all.