Maximum number of snapshots

Elastic Stack Elasticsearch
1

Does a limit exist for snapshots?
Can I have 72 snapshots of the same cluster? Can I have any issue in restoring one of those snapshot to the old cluster or to a new cluster?

I mean, in other situations forever incremental backups are very hard to restore because of too many merges to apply. Elasticsearch has a different approach, correct?

2

All correct.

You should consider a snapshot as a full backup. Meaning that you can remove any snapshot you want, it will have no consequence on the other snapshots.