Having to hack around the nginx paywall made me briefly consider going back to Apache.

Have you tried Caddy server? No affiliation just a happy user. It’s open source.

It may or may not be able to replace Nginx depending on your use case. For me Caddy has replaced everything I used to use Nginx for and more.

https://caddyserver.com/

I'm quite interested in Caddy. The last time I checked, things were in a rough spot with the v2 transition, but it looks like the documentation has improved.

Apache Traffic Server (no relation to Apache itself) would be an excellent option: https://trafficserver.apache.org/