You know that Platchat's top 10 list wasn't just the 4 of them. They got responses from like 10-15 people or something (they state as much when introducing it).
Also requiring them to watch every match each week on top of the casting and behind the scenes stuff they do, is wild.
Even with cutting out garbage time from every match, you're still talking like 20+ min per map, with 4 different regions overlapping you're looking at 400+ min or 6.66 hours when all regions are playing multiple times a week. And that's without giving yourself the chance to pause and take notes, write things down or just take a second to do more than a surface analysis of what's going on.
There's a reason they've been trying (and succeeding) to bring in talent who are familiar with the other regions when they talk about aforementioned regions. There's simply not enough time in the week to watch really take the time to analyze every game of every region every week.