For a while, meta progression felt like a clever way to keep games fresh. You’d unlock new gear, perks, or passive bonuses between runs, and that sense of forward motion made failure feel productive. I still remember how ground-breaking this felt the first time I played Rogue Legacy. The game nearly made me look forward to losing, limiting any frustrations I would get from losing. Over time, however, the novelty has worn off. More and more I feel like instead of removing the frustration, meta progression is removing the sense of improvement.
Having meta progression means that you come back stronger after every run, this completely blurs self-evaluation. You lost but you feel like you played well. Do you just need to unlock more stuff or are you not understanding something? It's really hard to say. How do you improve if you don't know how well you are doing? Losing is the usual way for a game to tell you you are doing badly, but this is thrown out the window in games with a strong meta progression. I personally often end up assuming I just have to grind more, which isn't a great feeling. And then, when I succeed, it doesn't feel rewarding because I know I only succeeded because of the meta progression.
Having this meta progression as a crutch also stops you from engaging deeply with a game's mechanics. Not only can you continue playing badly and win eventually, it is also hard to build fundamentals on what is essentially moving ground. Is 100 damage good? Now maybe, but that might not be true soon enough. I've recently had this problem with Ball x Pit, for example. I didn't engage with any of the stats because they all changed so fast that I didn't see the point.
I'm mostly referring to progression that makes you more powerful. I still very much like sideways unlocks which can serve to ease players into the game or to bring more variety in as the game goes on. I think Megabonk handled this pretty well recently, for example. Does meta progression still feel rewarding to you?

I have a very low opinion of "sidegrades." Games used to give you all their options up front.
This overwhelming trend during the past 15, 20 years to trickle-feed the player unlocks does untold harm. For one, players are rarely ever talking about the same game because everyone is at different points in the progression. The actual game doesn't start until the final thing is unlocked and this is often a place that most players will never reach.
Can't tell you how much advice I've read that goes something like "use X with Y" where at least one of those is locked behind 50 more hours of progression and my eyes once again roll all the way out of my head. As a developer, don't you want players to experiment with the things you put in the game?
Can't tell you how refreshing it is to play a game like NetHack where I can install a fresh copy and not have to worry about managing my save files because everything that's in the game is... in the game. Also, a quick study can start winning games much sooner because their options aren't all gated behind arbitrary time sinks.
But even just.. skin selection in multiplayer. Games used to give you ALL of them from the start and players could just, you know, pick the one they liked. This whole 'grind to show off how cool you are' is a dark pattern to coerce players to spend more time on the game than they want to.
You know what this is, is developers are catering to diamonds and they forgot that some of us are spades.
You describe while I can play Diabolo II hardcore, but get bored of 'rogue-lites' that have 30min or 1h loops.
You can always do solo self found for the "true" challange or do selffound for different experience.
The character is only reliant on itself and the stuff you find/farm. The "side-grade" comes from finding build-enabling uniques.
The antithesis to what you and OP are describing would be The legend of Zelda: Breath of the wild. But even fans of that formula are tired of it after 2 games in the series because as much freedom as it gives you, it‘s overwhelming.
I think what I‘m trying to say is that trends have cycles. They come and go. What you said is a valid opinion that I can kot possibly disagree with. However, these down sides become more apparent with time until we‘ve had enough and move on to the next thing. I am sure we‘ll remember most of those games fondly one day regardless. Nostalgia will kick in one day and we‘re able to look past the flaws again.
I just wanted to say, very interesting article! Thanks for posting
That link to the different player types was very interesting. I'm somewhere between an Achiever and Explorer. Probably more explorer, but I am a sucker for hitting the next level, gear upgrade, etc.