That’s mostly all it’s ever been.

There is also evidence that an out of court settlement happened between those companies. Notably moving away from cerebrates in SC2.

It has been standardized, but like most standard there are competing ones.

My phone gives me about 20 characters.

Cross platform games aren’t a buggy mess, everyone else has figured it out. Nintendo could do it as well.

There’s a few titles that have relied on gimmicks that would be difficult or impossible to do on other systems. It would be a temporary learning curve to get games able to support multiple platforms, but everyone else has already done it and Nintendo consoles have been the least powerful systems so it should be easier.

How many people buy Nintendo for exclusives isn’t super relevant. The important questions are how many more games would they sell if they were multi-platform, and how many fewer consoles they would sell if their games were available elsewhere. They would very likely sell substantially more games, but also likely see a significant reduction in console sales. This would still likely be a win as the games are far higher margin than the consoles.