For what synths the new content is for? Padshop? Halion? Groove Agent?
I am talking about the Bloom, Noir, Synthwave etc. content we got with the upgrade.
From the video I saw on youtube (non Steinberg) they are loops and one shots, so samples, not for any particular instrument. You will find them in the media bay.
The confusion I think stems, from previously, Cubase downloaded as one big blob, so you never really knew the names of the sample packs they installed.
Obviously, people moaned about that, many people, don’t need the samples, so shouldn’t have to install many GBs of data they will never use, so the new installer, splits out the packs and they are now optional.
If you look at the full download in the Download assistant, it makes a bit more sense. (plus shows which ones are for instruments)
What I find amusing is that Steinberg provided multisamples with the new packs, which are great, yet didn’t provide a tool which could benefit from them - because sampler track doesn’t support multisamples! 
Hey there, you can use Groove Agent for loading and launching samples.
It has a small but good amount of editing as well so it’s not a bad quick sampler 