1. Many indie developers will not actually be subject to the GDPR. The GDPR effectively only applies to non-EU controllers if they are actively targeting and expecting EU users, or if they are monitoring/tracking users in the EU.
The canonical reference to when that's the case is the EDPB Guideline 3/2018 on the territorial scope of the GDPR [1]. These guidelines are more narrow than widely perceived, e.g. that regional US news websites started blocking EU visitors is totally silly and unnecessary. Mere accessibility of a service, without offering the service to persons in the EU, does not trigger the GDPR.
2. If the developer does expect to be subject to the GDPR, they can hire a representative. There are many lawyers offering this service. It's not a terribly involved job, but it affects which member state's data protection agency is responsible. E.g. if you think Austrian GDPR interpretations are nuts, go look for someone in Ireland instead.
[1]: https://edpb.europa.eu/our-work-tools/our-documents/guidelin...