This is not on our immediate roadmap, but we’ve updated your topic to a feature request. We’ll pass this onto our team for future consideration and use the Votes from the community to gauge overall interest.
I don’t think it’s in Figma’s DNA to add services from other companies into Figma other than with plugins.
And I think Figma is already pretty heavy in terms of number of features. Figma is known for being easy-to-use software. And over time, I’m just afraid it will become another Photoshop with 3000 features that no one uses.
Even if Spline is an awesome software i vote against.