Hi

The Squash operation copies all the data and is no longer linked to previous commits?

Yes, basically the idea is if you have data version that relies on many parents that needs to be merged, the squash will create a merged copy and push it all as a single version, and then yes the parent versions are no longer needed

I thought this operation is like git squash but it seems to me

yeah... we did not want to actually delete the parents because unlike git, the operation is done on the remote head, so imagine the horror of mistakenly loosing all the data/versions by mistake.
Basically we left it to the user to delete the parent versions.
Make sense ?