The knowledge base has no single definitive answer that says all 2025 Plus models are locked to Synology-branded drives. What it does show is:
- DS925+, DS1825+, and DS425+ specs list compatible drives are mandatory and point to the compatibility list.
- The 2025 drive-compatibility policy excerpt says that for models released in 2025 and later, drive behavior depends on whether the drive is on the Compatibility List, Not Listed, or On Incompatibility List.
- A community post says third-party drives may work on DS1825+, but warns that if they are not on the official compatibility list, you risk losing Synology support.
So, from these fragments: 2025 Plus models are not described as universally locked to Synology-branded drives, but only compatible/approved drives are guaranteed and unsupported drives may lose support.
I don’t have a fragment for DS725+ specifically.
Sources used: [1], [2], [19], [21]