[Littlemaster]

How did you come to that conclusion?

There isn't much data in this review nor in your own (https://post4vps.com/Thread-Host4Fun-Rev...y-Host4Fun) to confidently make such a statement.

This assertion in your old VPS1 review thread is false:

Why?.. Because the /dev/sda device is a virtual disk and, by the look of it, I would guess it has a virtio_scsi controller, which -together with its friend virtio_blk- will always use the rotational mode, whatever storage device was actually used inside the VPS host.

See this 2009 discussion where the problem first cropped up:
https://bugzilla.redhat.com/show_bug.cgi?id=509383

Second, even if you run that command inside the host and the host is using a HW RAID setup, you'll still get ROTA=1 even if the RAID is based on SSD devices. Because in that case the disk is a construct(/an array) and it uses the RAID controller.

Conclusion:
The best way to know the storage nature is to ask the service provider as it's hard to tell the difference between an SSD-based storage and a HW-RAID-HDD based storage, from a VM stand-point.
[I tried it many times but the results aren't always clear-cut!]

The only thing that can make me lean towards it being an HDD-based storage is its capacity (100 G, but that's just speculation based on the cost..

https://ostechnix.com/how-to-find-if-the...-in-linux/
I have run cat /sys/block/vda/queue/rotational
Let me know if you find the command behavior is wrong.
We can't assume to a conclusion by cost or by asking the service provider. There is always a chance for wrong information.