A lot of the answer here is that MLB is ever trying to capture more of the "casual" fan market. They know they don't have to cater to the hardcore fans that support them, cause they are borderline addicts, and are coming back no matter how many times they threaten they aren't. (Yep, I'm sure a few people here can raise their hands there)
It's the fans that AREN'T watching that they want to get to watch, and to reach them, they have to do things different, because there is some current reason why they aren't going now. The most common answer there is the length of games...so that one gets talked about pretty much every year.
I was trying to find the data on how many actual innings were played in 2019 vs how many should be played if there were no extra innings, but didn't have much luck. That would at least lend some data to the arguments about the extra wear and tear on players and the messed up roster rules.
I dunno, 162 games is a little insane to me, especially since they are double the next closest sports basically. I don't have a problem capping them at 9 if you're going to play that many.
I just don't think extra inning games are that much of an issue. Putting the runner on second to begin an inning is an extreme shift from the way that very same game was played for nine innings.
MLB has been trying to speed up games for years. It's a slow paced game that is an acquired taste. I just don't see how this rule adds any value to the game or the experience of watching it. It's a cheap shortcut IMO.
I agree that 162 games are probably too many. However, since baseball is such a numbers oriented game, I doubt this changes.