Captains are a sole communication medium.
Captains do not need to end up in the team ultimatively, neither do they have to be present at every match. If our declared captain does want to play, they can pick 8 different players and declare a different captain.
Considering that in the past, all teams were created in a community consensus by figuring out together who will be in the team, we trust in the same mechanic here. Even if the captain delivers us the final player list and received the candidate list, most of them will decide by asking around instead of picking from their guts. Many will open a discussion publicly and make it a group decision as it always was. The only remnant is that the declared captain is our messenger.
We had several issues in particular communities being super bitchy about who is the captain, who gets in the team, even forming two parallel teams and I had to decide who ends up in the cup. This is bullshit and pointless drama. (Right Ryosuke-? You were causing this bullcrap in France last year)
Declaring captains as messenger and (in some cases) final call makers, we can avoid any sort of needless team creation drama and make everything run smoothly and fair. We always aim to pick captains that are reasonable, accessible and totally not focused on their circle jerk only. Being captain in the past without issues promotes you for the position, but does not guarantee it. The choices of captains will land on people that we consider to make the most fair and organized decision.
The individual registrations allow us to do the rule violation checks without crushing team rosters over and over again. We can avoid the entire hassle and move the team creation AFTER everyone was filtered. This avoids the 500 times of "I fixed my roster, here is the new". With this new approach, you can only pick from the candidates list and your team will be safe to be created in any case.
Moreover it allows countries to form teams that would otherwise never be able to create a team, because they are unaware of each other. We had potential teams of Mongolia, Israel, Venezuela, Vietnam and other places in the previous world cups.
Ah yeah, the only downside is, when less than 8 people pass the filters for a country. Usually the countries are weaker and maybe don't end up in the last 32, but sometimes they do. Then all players just get mocked up in one team and we declare a captain, but as always, they can switch around this position as they want. If you have less than 8 people in your country validly registering, there is not much to choose from a list...
OWC Grand Finals peaked in Twitch at #5 most viewed worldwide across all games and peaked momentarily to 16-20,000 viewers, having over 150 000 unique viewers across the entire tournament. (I should recheck that, I don't have the numbers in mind anymore)