I would argue not everything, just the things we remember. Those brands got popular, got sold and enshittified.
We remember these brands fondly (personally I had a JanSport bag all through elementary school) and that's why it sucks that they suck now but what we forget is now is there are 1000X more brands to choose from, some from megacorps trying to cut corners at every step. Some from small shops that genuinely want to make a great product.
The problem is visibility. Those good brands you have to go look for, you can't just go to WalMart or Target like in the early 2000's and expect to get a quality product. All the quality products now live on small websites scattered across the internet.