thing is though, think about it this way, if u were ALWAYS having to stay up to 2-4am for games (like most people in other countries have to apart from UK/EU/US for some examples, u will lose interest in watching BECAUSE they are on at such an inconvenient time for you.
what riot has done isn't perfect it's putting a band aid on a massive problem, but there's no real "good answer" to time zones, it's just how it works sadly, u can say "oh they should always do this bc this is where viewership is highest" but that's like looking at kills in-game and saying it fully decides who played well or not, that's just logically not how it works, riot want to include the whole world BECAUSE if they include the whole world, they don't have any enemies and on top of that, every country has sponsors wanting to sponsor them, among multiple other reasons those are just a few.
I know for some viewers who only think about the viewers this may be hard to swallow, but riot are looking out for themselves, not the viewers with these calls, as much as it's sad, it's how a business works and it's how a business will always work, Even other games like CSGO and Rocket league still host in different places for majority of their events, it's just how the esports business works, it's the same as the Olympics or the football world cup, people bid to host it, blank accept 1 bid and then that country hosts it, same concept here, i'm personally unsure if countries bid to host val or cs, etc but i can assume it's still based on some logical reason like exposure or viewership, etc why they end up going to different places, u also gotta remember u don't end up figuring out what the best course of action is without messing up and getting low viewership or low returns.