The rise and fall of OP indeed has the significance of a barometer for Ethereum's alternatives. Currently, all L2s are based on OP's chain, including Base and Sony. Any of these chains that have user transactions generating revenue will have to distribute profits to OP. In the medium to long term, this could allow OP to become a large and resilient ETH whale.
If conditions permit, it can actually intervene at any time to reclaim its tokens and further stimulate the ETH ecosystem.