Some of the asset managers have already submitted for SOL ETF and i am pretty sure it is only because they wants to be the first mover. I really doubt that SOL ETF will be approved. In my opinion, LINK is the suitable candidate for the possible ETF approval after ETH. SOL's demand and volume is fake mostly. On the other hand Link is going to be the universal gas token for the tokenized industry. If SOL ETF got approved other layer 1 like DOT, TON, KASPA can be the next candidate.