on the announcement, Sep 15, Adobe stock fell by 17%. the FTC opened some investigation on Nov 2. some EU thing started its process in February (based on filings by refering countries, and of course we have no idea of the details of those country-level processes)

so, all in all, it's likely that relevant authorities quite soon signaled that Adobe-Figma is facing an uphill battle, and now, as they announced, they backed down.

we have no idea of the negotiations, who was fast or not, who recommended what, asked for what guarantees, and so on.