Seems like a complaint that MS was using underhanded tactics, so Kaspersky complained to an organisation that might do something about it.

It doesn't really seem like an example of MS coming up with a better solution then discussing it with industry, unless I'm misunderstanding it?

Instead it seems a lot like MS figuring out a solution that advantages themselves then just rolling it out, at the expense of others. (?)

As someone that worked at MS, on a team that worked directly on this issue (among other things) some years ago, MS did figure out better solutions and did discuss it with industry.

MS has an entire forum for discussing these things with industry (https://learn.microsoft.com/en-us/defender-xdr/virus-initiat...) and has had variants of said forum for some time (I think the first effort was in 2010).

Kaspersky was running an SSL/TLS Proxy in the kernel IIRC and didn't want to have to move it elsewhere due to the fact it would require them to rework their product quite a bit.

The solutions MS (we) proposed were agnostic and overall better, the anti-malware industry simply doesn't want to make the changes as these things do impose technical work on existing products.

No worries. That wasn't at all evident from the above complaint.

Was the drive for this industry forum coming from dealing with the EU, or was it more from MS trying to make things better without needing the prodding?

Industry forum was external, MS did not start that.

I do not know enough to properly answer on the concrete reasons why, only that it was external. Sorry.

As opposed to Apple, who's gone and just done that for their operating system?

Apple isn't (yet) a convicted monopolist, though it seems like there's a strong case to be made about just that. ;)