I have a caveat on my vote - I chose to vote for this as I believe if I vote against it, my actual opinion will not be seen.
I do NOT want separate leaderboards or even a leaderboard at all for lower leagues - I also believe, if possible, this is only really something to consider for Bronze/Silver, as it would go a long way to providing a safe haven for the 500k marketing campaign we may or may not be doing soon to onboard players.
I currently play in Diamond modern, so this does not affect me personally in anyway:
I think we should be treating Bronze/Silver as a more casual experience to the game and tailoring their respective leagues to be a place where these smaller, casual players exist - I believe this will make it easier to onboard a wider variety of players in the future, and make the 500k marketing campaign more effective, should it come to fruition. I would also argue that this change should be Modern Only as if it is in Wild, bots will be able to anchor to a lower league and optimize their SPS stake
This is different from a modern player doing that - as a modern player will consistently need to engage with the current set and purchase it, creating yearly revenue for the team, regardless of what league they play.
That being said - if I vote against it, it will be seen as no to league limits as a whole, so my vote is for.
Mostly agree with you except in two parts:
gold league is a significant mid-level investment, I don't think it should be ignored or grouped with diamond. If modern is going to need constant investment, then silver-> gold is a significant upsize. as is gold -> diamond. Silver -> diamond may seem impossible. Giving smaller goals makes progression feel possible.
IMO there's no need to completely remove the leaderboard itself at lower leagues - people still want to feel competitive. But rewarding with glint instead of DEC or SPS will limit the economic incentive to camp.