Oh I totally agree they bought Figma because they couldn't figure it out themselves and to protect the products / revenue streams they already have.

At some point in the future after designers have gotten tired of Adobe Figma, some new product will offer something that Figma is failing on and take the market. However,

(1) that something won't be multiplayer web based collaboration - Figma has solved this one. The killer feature will have to be something else

(2) In all likelihood, Sketch won't be the company that does this.