They were shitty because they were so easy to make so everyone was doing it. But when they were good they were really good. It’s hard to overstate the number of novel game mechanics spawned during that time that are still fueling the mobile game market.
In a similar vein, auto chess came from DotA2 and now TFT is this massive game. But its origins came from is line tower wars and Pokemon... something (where you upgrade a team and battle other teams) from WC3. There's a massive pool of creativity that's untapped and can't mesh with Main Social Forum because of copyright and other ways of capitalizing the Internet