I’ve used S3 primarily in a professional setting but R2 has been a breath of fresh air on my side projects.

The zero egress cost is big and IMO their free tier is very generous. It’s S3 compatible so if you use any libraries it’ll just work™. One note is that AWS recently released static pricing for Cloudfront - I haven’t explored it in depth yet but it looks compelling if your primary use case is serving data out of S3.

I’d probably switch to S3 at least for app storage if I moved apps into the AWS ecosystem. It’s just easier if you’re already in AWS.