What are some mechanics you remember that just don't get made anymore?

It feels like game mechanics for TRPGs come in trends. Someone makes a new mechanical concept and, if it takes off, it can become a frenzy of using said mechanic to do the usual genres: fantasy, sci-fi, superheroes, cyberpunk, etc. Eventually, the trend cools down. A new mechanic becomes the new hotness. Etc., etc.

What are some mechanics you've noticed have vanished completely from newer games that used to be everywhere?

What sparked this idea for me was looking over an older game, OVA, and remembering when everything used Advantage/Disadvantage. I don't mean the 5e mechanic -- roll 2d20 and take the better or worse result -- when I say advantage/disadvantage. I'm referring to building a character partially by selecting a list of advantages and disadvantage, which are essentially perks/powers/stunts/class features/etc. that are typed as good and bad respectively. You'd have long lists to pick from each category and were often required to pick at least one disadvantage to add depth and flavor to your character. Savage Worlds seems to be that system's last flag-bearer, which its official and 3rd party content still using that system.

Why did it die off? To my knowledge, it was two fold.

Adv/Disadv were usually easy to exploit. Gamers quickly would discern which disadvantages could easily be mitigated and which advantages could provide the strongest benefits. This issue was buyoed by the tendency of systems at the time to hold mechanical and narrative benefits/drawbacks as equal. This false equivalency often led to people taking mechanical advantages and narrative disadvantages to maximize effectiveness. Even more so, some narrative disadvantages could even be seen as advantages in practice. A nemesis is a classic example of this phenomon since having a nemesis often meant you just got more "screentime" and attention. Sure, someone was gunning for you, but you got to be important and people like that.

I can also think of Lifepaths being a once popular mechanic that died off.

Lifepaths would work by having you create a character by deciding what they did at certain stages in their life. How their childhood was, what they were like as a teenager, whether they went into the workforce or went to college, etc. With each choice, you'd slowly build your character out with stats, perks, flaws, etc tied to each decision. You'd often be free to choose how old you could get, with many games giving younger characters more flexibility to compensate for older characters having more experience.

This similarly died out and my best guess is that it came down to complexity and balance. Tabletop RPGs are already competing with a lot of things in your life: work, school, TV, movies, video games, music, bars, parties, restaurants, etc. As technology improved and companies became ever more focused on "engagement" as a means of making money, it got harder to sell more complicated games in the wider market as people wanted something easy to get into and easy to play. There definitely was a strong "simplification" trend in the industry from about the 2010s to the 2020s. I feel it only recently has begun to turn. I do use the term simplification relatively to whatever came before for said genre/system/etc.

However, even before then, I feel Lifepaths died out in the early 2000s when the d20 boom and the relative simplicity of race/class just made it seem "easier" to just jump into a game, especially since the d20 system was so ever-present. The more drawn out process, especially with games often not making it past a handful of sessions, become unattractive. Not helping matters was that, often, the attempt to balance older characters with younger characters was usually wonky and didn't work as great in practice.

Those are just two mechanics I can think of that sort of were everywhere and then died off. What trends do you remember? What do you miss? Why do you think they died? Do you ever think they might come back?