I've run pihole for years. It works really well. The only problem I've seen is when you actually need a tracking URL to work. For example clicking a link in your emails to download a ticket for a concert. You just need to be mindful that when the browser fails to open a link it's because of the PiHole. There's no nice screen telling you. You just need to pop it into the whitelist to allow it although on a phone I just used to go to mobile data temporarily, click the link and then go back on WiFi.

I recently switched to using NextDNS, as it means all my DNS queries are encrypted and I still get filtering when I'm away from home. I also have three kids to manage so it allows me to set timers on their devices to block certain traffic. Good for blocking adult sites too.