The issue with custom ROMs is the support for devices. I had to buy a new one from eBay to install LineageOS and I didn’t regret it. I use now 2 phones, one for privacy (I use it 80%) and the old one for mail and whatsapp (I’m forced to) to contact my family and friends but that’s it.
Even so, you never knowif they’re really no log. What guarantees that apart from a verbal promise?