We could also see more rich people join in as well. Look at premier league, even a team like Newcastle is owned by rich people, and not doing great. This means that teams could reach a point where most of them are owned by wealthy people, and in that case, it would still be "equal" in a way. Yes not like the old days, but it would be not so much gap.
Like for example, PSG is richer than all other teams in France right now, but there are some gossip about teams being sold to other rich people, Paris FC was sold for example and growing, maybe teams like Lille, Monaco, Marseille would be sold too, and create some competition for PSG as well. What's so bad about rich people buying up teams, I rather see them use their money that way than tax evasion.
Tax evasion is the task of every responsible citizen. And what taxes are you talking about if the Premier League clubs are bought up with oil money from various dictators?
As for development, it is very uneven - look at the gap between the EPL and the Championship. The EPL is literally a Super League and there is no rotation with the Championship because there is a gap between them. And this unevenness lies precisely in oil money - if they are removed, then the financial fall of the Premier League will be catastrophic, perhaps at the level of Barcelona.