It's hard to know from your post why the pool was closed. If it was closed down for planned repairs/renovation, then perhaps it would have been appropriate to put a notice on their website or contact the incoming guests. If the pool had recently broken down or required some unplanned maintenance, then contacting all of the relevant guests may not have been feasible.

The hotel did make arrangements for the guests to use another pool, even if it requires driving or being driven there. If you’re not looking for any compensation (which, as an elite member, you would probably get) what else do you want?