In France, you can, in theory, buy with BTC, but you have to pay taxes and notary fees in euros.
Since you also have to pay capital gains tax and (unless I'm mistaken) prove the origin of the bitcoins. Justifying the origin of funds when you won cryptos with games or airdrops and then sold them to buy btc 15 years ago is almost certainly impossible.
It's almost impossible to do because bitcoin is not allowed to be used as a legal tender, so buying a house with it is a problem.
Most countries see bitcoin as an investment asset and it is regulated and allowed, it is impossible to use the rest for anything else if it is not allowed.
Taxes also vary and maybe each country has different limits, but buying a house with bitcoin especially in my country is not possible.
I don't know how France manages taxes because I don't live there, I'm more interested in buying bitcoin to save.
While the method of buying a house can be simplified by selling bitcoin and then converting it to fiat currency, so the problem is easily solved.