Manjaro puts a lot of software in their repos that Arch does not. As you found out one of those things is the Brave browser (much to the dismay of several Manjaro forum members.). This leads to Manjaro repos being bloated by Arch standards. Manjaro also modifies several apps before placing them in their repos (octopi is one). Many would say that manjaro is based on Arch , but is only Arch-like, while EndeavourOS is closer to pure Arch.
It say’s a browser that stops ads and tracking by default? I installed it and it wants you to watch their private ads to earn rewards. Hmm? I want ad free…tracker-less! I’ll stick with the real Firefox!
Nothing’s wrong with having more support if it’s available. With non-commercial endeavors, support is via volunteers. The main support staff have their hands full. Nice-to-have-software volunteers are hard to come by, usually only support what they are interested in, and may not be long term. The linux landscape is littered with orphans.
It doesn’t ask for your root password at start but it asks for it after it compiled the package to install it on your system. (depending on how many packages an app has, it sometimes asks for your password twice) That’s why it is vital to stay near your machine when running Yay, otherwise you might end up not having the package/app installed.