The knowledge base does not have a complete answer to your question.
What it does contain:
- DSM 7.2.1-69057 Update 12 is an important update that fixes multiple security vulnerabilities and restarts the device. It notes that the update may not be offered immediately in all regions. [2]
- Synology Application Service 1.8.3-20742 requires DSM 7.2 or above. Earlier package versions require DSM 7.1 or DSM 7.0 depending on the release. [1]
- One community post says some DS918+ users considered DSM 7.2 to be not automatically offered, and that manual installation via Synology’s download area may be possible, but that post does not provide a full compatibility or removal list. [14]
- Another community post advises that major jumps from 6.2 to 7.x should be approached carefully, with backups made first. [13]
What I cannot confirm from the fragments:
- The main feature changes in DSM 7.2
- Which apps break or are removed
- A device-specific recommendation for your model
If you want, I can still summarize only the verified points above for your specific DSM/package version path, but the knowledge base has no fuller answer yet.
Sources used: [1], [2], [13], [14]