I have a pretty clear idea about this way of deletion indeed: it is a really bad idea. The reason is that you need to look at the dependencies between data and log backups. The only clean way of deleting log backups is to figure out what is the oldest data backup you want to be able to recover from; then, based on this data backup, you can determine all log backups that are not needed anymore. That's what my shell script provides.
On any database, you have to either disable log backups, or implement a backup management strategy. If customers don't do this, they will run into problems. That is not the fault of the backup system, but of the implementation team. Since the beginning of HANA, you could disable log backups. The script that explains how you have to and how you could manage your log backups exists since about two or three years now, I cannot remember. The mechanism in HANA studio to manage data and log backups is also around two years old, now.
Best regards,
Richard