Sure, but such a scenario is 1: highly unlikely (and OP never bothered to clarify their thoughts on this) and 2: just because it would take a long time, doesn't mean it wouldn't still occur. That's not the same as 'unreachable', not even by a long shot.
The cascade of lower profitability per day due to longer block times makes it possible, and also while it would still theoretically occur, if it takes 10 years to get back to 10 minutes block times, bitcoin is as good as dead for all practical purposes.
Paint me a picture of situations in which the above may occur in the Bitcoin network, assign a probability factor.
If BTC price does not at least double by the time the halving happens, then a good chunk of the miners will be turned off with a 100% probability, either pre-emptively or through bankruptcy.
Only the efficient facilities show a profit with current price and reward these days.
So this all boil down to whether the price will reverse its current trend until halving, the probability of this being unclear at best.
it just would never be able to get through those 20160 blocks in any reasonable timeframe
Emphasis mine - that's not the same as "not enough hashrate to solve new blocks"
Actually no, at some point miners would just give up and the blockchain would be stuck until a hard fork artificially and immediately reduces difficulty.
This is not hypothetical, this has been happening to altcoins.
Since most miners are in it for profit, once profitability falls because it takes too long to find blocks, they just move on, which makes it even harder for those left, until almost no one is mining anymore, at which point no new blocks come out and are solved (or if they are, it's with many days between them), eventually resulting in a dead blockchain.