I mean personally, I'm OK with just continuing to use Excel. If anything it'd be nice if they made newer APIs. I actually like COM for some reason, but it does feel dated at this point. I bet there are some other APIs, but I'm not in the biz of writing Excel plugins, so I'm not up to date on it. I did it once for fun and never spoke of it again.

But basically, I kind of just want a simple API for interacting with workbooks and providing functions, maybe using embedded JS or Python scripting. That, to me, sounds like it would make Excel a lot more palatable toward developers like it is toward end users. (Honestly, I think what I'm describing is a bit like WebExtensions but for Excel workbooks. I'd dig it.)