most people won't make much here, most won't become dolphins, they won't become whales

I think, it would be a over expectation to wish to become whales without any major investment , if someone starts now ( unless, he has brilliant content and puts a lot of effort to build relationship for at least more than a year).

Coming to dolphin, yes, it should be achievable, based on what you advised. However, what I point out is that, slowly more and more dapps are evolving which provides means to earn decent amounts at least. So that is a lot of encouragement and based on what I see, we are going to see more and more such dapps and new communities, which will attract people.