Nowadays I consider BTC as a pure speculating coin. Because the volatility turns this cripto not suited for being used on daily needs.
In comparison to what, fiat or other cryptocurrencies? You have to understand that if bitcoin falls 5%, shitcoins fall 10% or 20%. If bitcoin falls 20%, shitcoins fall 50%. So, if bitcoin is bad for you, which coin is optimal in your opinion?
You're right to a large extent. Bitcoin isn't a means of transfer of value in a practical sense. Imagine paying for an article and waiting 10 days for delivery because the merchant hasn't received their payment.
Nothing prevents you from checking market conditions before sending a payment an paying a high-enough fee to get into the next one or two blocks. Plus, there is the option to bump the fees if needed.
I have transactions that are pending for more than a week due to network congestion.
Because of an incorrectly set transaction fee. It's true that the congestion went crazy a few days ago and that you needed 500 or more sats/vByte for a quick confirmation, but that's no longer the case. If your transaction hasn't been confirmed by more than a week, you didn't do a good job to check the market conditions.