Top 10 moments in gambling history: milestones that changed the rules of the game?

I can't think of a top 10 but in my personal top are, in no particular order:

• NoLimit City's feature spins - for which they have probably taken inspiration from the likes of ELK Studios. I think that some of the games with this type of feature have the real potential of hitting a really big x, unlike other games that say "maxbet = 100000000x"
• BTG's MegaWays feature - although multiple studios began using a similar type of feature, the first one stands out the most, since it's also pretty much the most used by other software providers
• EGT/Amusnet's jackpot system - even though it exists on other games, this hits closest to home in my experience, coming from a country that plays games from this software thanks to their big jackpots that can hit on any denom & bet size
• Novomatic - probably one of the first providers in my country, no remarkable features or anything like that, but being one of the first to penetrate a market the size of my home country leaves its mark

Idk about others but these are the ones that I can think of off the top of my head right now

There's a dedicated article on this topic: https://chipy.com/news/top-10-historic-gambling-moments-milestones-that-changed-the-game.