Could've sworn I offered my services pro bono last summer while I was out of work, as I was doing JUCE help for another small vendor at the time. Maybe the email bounced.
As someone who has done a fair amount of DSP coding on three platforms (macOS, Linux, Windows) and in three computer languages (C, C++, Java), I can vouch for the platform issue being primarily related to GUI stuff, and to a somewhat lesser degree the VST spec -- all of which JUCE takes care of!
At any rate, I spent a few hours last night with the OB-E demo, going into single-voice mode so I could compare directly against SEM-V and the Brainworx emu, on custom patches I came up with on my own (as most of the presets suck for all of these VI's).
OB-E blew me away with its cleanness, three dimensionality, organic phrasing, etc. Also, it was musical at almost any setting; whereas I find it really hard to get SEM V to sound good on my own presets so I usually search hard for cherries in the preset packs.
I'm not going to buy it though, as I've noticed a trend where several vendors release similar products in previously uncompetitive spaces, all within a short span of each other. More often than not, I like one or two that come after the "early bird". My guess is there's a lot of industry leaks, and some vendors rush to market as it can have a big impact on overall sales.
I wouldn't hold my breath on this one being available for Windows, based on what has been said so far by all parties (including the vendor). What I mean by that, is it's long-term not short-term.
I'm currently on macOS but have been seriously considering switching to Windows due to the pandemic, as I find it harder to do development work on a Mac, which didn't matter pre-pandemic when I went into the office and used Windows Remote Desktop on the Mac. I am holding off on buying single-platform products as a result.