There's no real advantage to joining the largest instances, you can view all their content from your fediverse account regardless of which instances you're on (unless it's been defederated which only applies to a small number).
Too many users/ traffic can overload the servers reduce the experience for everyone. Instances are mostly hosted by individuals and becoming too large, too quickly could have a financial impact on the owner.
Additionally, if any instance ever gets too large a share of users on the fediverse, the way they operate and their rules become "the standard". Then we're basically back at Reddit.
Diversifying instances is good in the long run!
I thought "feeling like a man" meant eating a lot of meat and losing money on sports betting.
Idk I don't do traditional man things.