@elena It runs fine on my Pi 2B (so older/slower than yours).
It can get limited if you load a lot of blocklists. I use a handful from the excellent Hegazi - https://github.com/hagezi/dns-blocklists.
Haven’t done extensive testing. But some ‘dig’ commands showed query responses to be under 10ms. Which is healthy enough for me.
I think you’d be fine unless you had demanding requirements.