This is the chart of Bitcoin's Avg. Transaction fee:
https://bitinfocharts.com/comparison/bitcoin-transactionfees.htmlRight now the median fee is about $2. After lots of halvings the reward won't be enough to satisfy the miners. I guess that after a decade, bitcoin will be more widespread, as a result, more transactions will occur every second. Won't this increase the median fee? If it does, bitcoin will start being a not-so medium of exchange. Imagine paying $5 for a transaction. Even paypal doesn't charge that much.
There is no point in thinking so far distant into the future.
While it is true that mining gets more and more difficult over time the transactions fees won't be the only thing which will factor that. As such, it wouldn't make sense to have the types of fees your describing as as you have alluded at people won't be happy to pay that much, or will they? Only time will tell.
I think what's important sometimes is to focus on what's in front of you and right now I say let's enjoy the BTC bull run
