It would be interesting to know the negatives of Synology, and why did you move from them.
Gaining nothing from your comment, it could be that your boss was pissed his ex- got a job as security there.
My biggest reason is flexibility in machine configuration. I found a lot of flexibility in bringing my own machine to the table. I can set any mix of HDD or SSD or Nvme or ram in my machines. With synology or any other premade box I am stuck in a specific config.
For example my current TrueNAS at home has 128GB of Ram, 32TB of NVMe (live data) and 72TB of HDD (archive data) with significant cpu and gpu (well compared to synology box, I am running a Ryzen 5700G) and 10G networking.
It didn’t start out here but because TrueNAS works with your own hardware I can evolve myself incrementally as hardware costs and needs change.
It is a beast of a machine and it is no work to maintain - TrueNAS makes it an appliance.
