I always use a VPN to connect to the internet. I don't really care that my Internet Service Provider (ISP) might be spying on me really, for the logical reason that it is very likely that most of my devices are actively spying on me to get data to target me for ads.
My issue with connecting to the internet is that my own router can be hacked, and from there, any malware or unwanted access can be done to any of the devices connected to this router.
By using a VPN that blocks malicious traffic I protect my devices in two ways:
The second point can be seen often! I like to play online and competitive games, but some players found a way to get the opponent's IP address, and with the IP address they send a DDoS attack to disconnect the other team and win the online match!
It is uncommon because a DDoS attack is not easy, but it is something that happens in online competitive games! So by using a VPN I make it harder for the other players to get my real IP. They can still DDoS the VPN server, but that is a lesser problem for me.
Also, there is the reason that whatever my ISP provider can see about me, I am very sure that my VPN provider can also see! So using a VPN for privacy would be a leap of faith. But for security, it makes total sense.