I frequently read that people at the time said the plastic minis in Nemesis can detract as much as they can add to the atmosphere, hiding important parts of the board space owing to their sheer size.
TI is often lambasted for taking an entire weekend.
Rosenberg's euro games are the bane of many a player trying to keep all possible actions in their mind.
Modern kickstarters can arrive in shipping crates worth of stuff, making you rent a lorry just to get your 25 minute party game to a meet-up.
What's your biggest regret purchase you can readily recall where a game was just "too much". No matter what specifically it was too much of.
For me personally, my big one was Android: Netrunner. I was excited to jump back into 2-player competitive deckbuilding after I quit Magic The Gathering early in the fourth edition. And it seemed so perfect. No luck involved, known spaces of cards, multiple factions, asymmetry which I nearly always love, it's all perfect!
On paper...
In reality I found out, yes, for me this is a strictly superior MtG. No downsides. Except that I'm no longer 16, and I no longer want to spend forever creating decks, collecting cards even if they're not random, or engage with sifting through hundreds or thousands of cards when working on decks. The exact things that made me excited to play MtG-but-better and brought me to buy Netrunner were the very things turning me away from it now.
Still got to sell it, oddly attached to my first-run box + all expansions now that it's no longer available. But played it like 6 times and that was it. 0 enjoyment. Gave actual MtG a try, even less enjoyment. Tried Keyforge, also even worse. I feel that the entire genre is just a goner for me, and I regret investing so much money into Netrunner. A lot.