And why would you trust your own ISP more than reputable VPNs?

Sure, this statement is very valid for (free) VPNs which are not reputable, and act as data mines instead of providing true privacy; but your statement reads very much like we do not need VPNs at all.

ISPs know what sites you are visiting and when, and they are ready to comply with the government. Also, we have acts like Online Safety Act (UK), which incentivizes more data collection. Combine that with age verification on every site, and you are basically giving away your browsing history.

I agree that a VPN alone is not going to protect you, and you need to authenticate less into websites, and clear your cookies after every browser session (basically good OpSec). However, I also think that reputable providers like Mullvad and Proton are a must.