I checked my VST3 folder… the most space required, the NI stuff, followed by the Arturia stuff.
It all comes down to NI again.
And some vendors installed the AAX plugins with no way to prevent it. It costs 2.3 GB on my system, without any need. The same goes for some VST2 stuff.
But we discuss this in the Steinberg forum…
We should make the vendors aware of these “issues”.
I’ll prepare the helicopter, there’s some dog poo in the black bags on the grass over there… Let’s go!!
…They won’t dirty our C drives again. 
At one point, if Steinberg allows to choose the VST3 folder, and to move it to an external SSD, I don’t have anymore issue
But this will not happen, since it chooses a system folder at the moment, and I can’t imagine that this will change.
Symlinks may offer a solution? (Win10 also has symlinks)
I got a response from UAudio stating basically “we’ll see” with updating to VST3. I have a pantload of UAD plugs and I will be livid if they don’t progress their plugins. They shouldn’t be playing with fire as other manufactures are getting better all the time. The CPU isn’t the weak point it used to be.
G-Force is updating their current catalog, but not ETA when they’ll be ready.
I will miss Motu Ethno. No plans to build VST3.
honestly… I don’t think so, these problems with VST3 have been around for years… so 24 more months won’t make a difference.
I tried Symlinks but unfortunately without success 
You’ve put “we’ll see” in quote marks. Did they actually say that, as it seems unlikely? It’d be great if you could post their actual response, no paraphrasing etc 
You can use Blue Cat Patchwork to open M1 Native VST2s in C12 in Native mode. They have to be native plugins of course like nearly all of UAD so they will work. I loaded up a Ampex UAD tape and it worked in C12 native mode. I also opened superior drummer 3 and copied some grooves onto the Cubase track and played them.
Patchwork will not allow rosette converted AU plugins in C12., well I could not get that to work, it just hanged.
But it means I can now use all of my VST2s while I wait for the developers to release VST3 versions. It is a little messy but you can save presents of your fav VST2 native FX or instruments to make it neater.
There’s a Noisemaker VST3: https://tal-software.com/products/tal-noisemaker
Dexed has recently become available as a VST3 … yay! 
Some of them are now VST3 :
Thanks Stuart.f for TAL Noisemaker
and MrSoundman for Dexed
Tunefish4: Download Free Additive / wavetable synth plugin: Tunefish 4 by Brain Control
Pendulate: https://www.eventideaudio.com/plug-ins/pendulate/#pendulate_giveaway
Tyrell N6: Freeware Synthesizer Tyrell N6 Plugin VST, AU, WIN, MAC - AMAZONA.de
Still VST2 new list:
4Front Bass
Ample Sound : ABPL2, AGML2, Ample Guitar M, APC
Alan Vista: Chau gongs, Marimbaphonic, Royotoms, Thai Gongs
all Bigcat instruments
VK1 Viking
Daichi Synth1
Datsounds and Lostin70s Keys instruments
Keolabs Spicy guitars
Manda Audio MT-PowerDrum
Some NI plug-ins, including Guitar Rig, but I can’t imagine they won’t upgrade them in the next months
This latest update from Soundtoys:
“We are currently finalizing the VST 3 versions of our plug-ins and expect to have them available for public beta very soon.”
… albeit the Tyrell N6 VST3_ReadMe.txt file for the Windows version current as of this writing (TyrellN6_V303_Win.zip) seems to contain a number of caveats, (excerpts):
Important information about the VST3 version
…
Known issues with the VST3 versions:
- they don’t report parameters on preset changes
- in Wavelab, they show symbols instead of registration info
…- they don’t show the selected patch name when a project is reopened
…
Will the Korg Collection ever go vst 3 ??
all the Best
John
Apart from the fact that this is the wrong place to ask this question …
opsix native and wavestate native from Korg are VST3 plugins.
As Steinberg keep telling us this is a USER forum - and it seems a very reasonable question in a thread about VST2 plugins without VST3 versions IMO. Usual friendly SB response though…Mods deleting any threads about the dropping of VST2 support (thanks @steve - usual heavy hand at work)
That may be true but neither of those plugins are part of the Korg Collection v2 or v3. The correct answer is we don’t know…and if they do it may well be a paid upgrade
Speaking of which: Toontrack have announced EZdrummer-3 which WILL be VST3. They went on to say that there will be NO further development on EZdrummer-2. I think this was fairly predictable and will be true for many of the developers ‘upgrading’ (ha!) to VST3. So those who want to upgrade to future versions of Steinberg products are liable to need to spend many more $$$ to continue to use the plugins that they own and use today.
At least the smooth and stellar upgrade that is Cubase 12 shows that it’s all worthwhile 
Yes, this is a USER forum and for sure a very reasonable question, but as pointed out in my perhaps too flippant command above, not worthwhile. At least not here!
Have you or JohnS contacted Korg in reference to the VST3 support of the Korg Collection already? What is their answer?
Opsix and wavestate are indeed not part of the Collection but it shows that Korg is willing to support the VST3 interface and now it’s up to you to show them (Korg) that there is a huge Korg Collection community, waiting for VST3 support.