Payments of this nature using the layer 1 blockchain are not super feasible, as you say. (Although I've made several online purchases using BTC and it works quite well.) However, layer 2 solutions like the Lightning network do allow for extremely fast and cheap transactions, then they use the slower layer 1 blockchain for final settlement later.
Cryptocurrencies have three main attributes that affect their usability: Speed, Security and Costs. You can pick any 2 but there's always a tradeoff with the 3rd. For example, BTC chooses to prioritize security over everything else. This results in it being slower and sometimes more expensive than other crypto, but that extreme security is what makes it such a good store of value over the long term.
If you want faster and cheaper transactions, you can use other cryptos like Solana but the security and reliability is no comparison.
You're right, you may never use layer 1 for everyday transactions but there is nothing better when it comes to storing and transferring large amounts of value. So just sell a little BTC every now and then and convert it into whatever currency you need for everyday use, whether that be fiat or some faster, cheaper (but less secure) cryptocurrency.