Kudos for mentionning powerDNS, it’s an amazing software :)
One thing I love with powerDNS is the various backends available, notably the postgreSQL and mariaDB/mysql ones. Only the primary powerdns instance modifies the database records, the secondary instances just read from database (master or replicas). Thus, no real need for AXFR: as soon as you added/modified a record on the primary, the secondary pdns servers will see it in the database.
The pdnsutil CLI tool is also really convenient, and the powerDNS API is a godsend when you need to automatise stuff for thousands of domains and hundred of thousands of records. There’s also a nice third-party webUI (powerdns-admin, docker image: pdnsadmin/pda-legacy). Bonus, Terraform does have a powerdns provider.
At work we use dnsdist (from powerDNS too) to load-balance between our powerdns instances (with caching!), and to filter out/rate-limit/temporary ban bad actors (dns laundering, records enumeration and such for example).