How is a pi (or other single-board computers) less critical than “a full system”? Do you have any idea how many pi’s are out there running serious stuff? Where I work I bump into them all over - including in security systems and door-access.
This one has two 2.5gb ports, 8 to 32gb ram. This is serious stuff for an sbc, clearly overkill for your pihole install. What’s not equally serious with banana pi is support. I went to their wiki, it lists Android and Debian (previous version) “images” but no download links, so it’s hard for me to verify that this board boots with sshd running or not. Like I said Debian does not, and for a good reason. Raspberry pi os pulls from raspbian, and they pull from Debian.
You can run Ubuntu LTS, fedora or others on your pi.
The telemetry is bad news - soon we will be out of food because someone knows what size of sd-cards you use, and the number of installs you do. So better go buys a silly board, track down some ancient image of an install someone did at some point where they managed to compile the nic drivers and include the binary blob. Because nobody gets to force you to add an empty file to your sd-card!