> Fundamentals are about long-term investing and growing money over time [...] Day trading is about speculation
What you call 'day trading' has turned into week trading, has turned into multiple-month trading, and I would argue even beyond a year now in a lot of cases. Plenty of stocks have been pumped far beyond what their 'fundamentals' would justify. In some cases, that has changed the trajectory of companies and even entire sectors.
> in the long term, GME's value hasn't changed
This is entirely debatable. The investors just changed it, and new people are on the board who could potentially turn it into an eSports empire, or the next Valve, or who knows what else. Not at all likely, I know, but money changes things and there is some amount of 'true believer' investment happening, like we saw with Tesla.
Honestly, I don't like all this volatility one bit. I am increasingly concerned about not ending up homeless when I'm elderly. But the fact is, the market appears to be changing, and so-called 'retail investors' may be gaining new prominence in the greater order of things. Valuations based on hopes for what could happen 30 years out instead of how much paper profits got jacked up over a 3-month period. It's scary and I don't like it. But who knows, in the long run it could be a good thing? I don't think you, or I, or anyone else can say from here.