IMO ECS is in a weird position right now, because:

1 - It's simpler thank K8s, but not that much simpler than your avg managed K8s offering

2 - It really locks you in the AWS ecosystem

3 - It is way less used than K8s or just running things on servers, so there are way less help / learning resources

I really don't see how using ECS is much better than EC2 + compose for small setups and this post didn't provide many good arguments to convince me.