None of those pool miners are forced to use the pool.
The thing is most miners do NOT know about this, or they have no idea that this actually affects their profit, and since nobody has complained about it, the pools think it's okay to do it.
My guess is a sender will only do it one time and never make the mistake again.
Transactions get stuck for so many reasons, some wallets miscalculate ( or rather misestimate) the best fees to be paid, transactions with higher fees could show up in a few seconds right after your transaction is broadcasted, in many cases, you pay enough fee to be included in say 1-6 blocks, suddenly BTC price fells, people rush to send their coins to DEXes and wala, your transaction gets pushed down to the bottom of the list.
However, I do agree that it isn't something that happens in every block, maybe no even every day, but it does happen, profit loss is profit loss, whether it is 1$ or $1000.
So my guess is the paid one is not used much.
I think we can get a rough estimate by extracting transactions with very low fees that get accepted in blocks full of other transactions with a lot higher fees or when there have been higher fees transactions pending.
Example:
Block 111111 contains 20 transactions paying 5< sats, all other transactions paid 50 sats, and the mempool at that time had 100,000 pending transactions with 50> sats, those 20 transactions can be "assumed" accelerated, and the minimum loss of miners would be :
(The total size of those 20 transactions * 50 sats) - (the transaction fees for those 20 transactions)
To get the maximum loss we can do
(The total size of those 20 transactions * maximum fees pending at the time of the block) - (the transaction fees for those 20 transactions)
But that will be a lot of work, the easier approach would be getting the average fee and any transaction that has a much lower fee is to be assumed accelerated, this will have a lot less accuracy but we can at least can an estimation of how much miners are losing, because as it stands right now, we don't know, it could be 0.5
BTC a week, or 10
BTC a day.
Moreover, it's more than just the "lost" profit that comes as a result of including the transactions of low fees, it actually the profit that these pools generate, they charge A LOT more than what you could have paid to be included in the next block, so the profit is big and miners should be the once earning it not the pool.