Adobe hasn't bought Figma yet - they're waiting for government approval and hopefully the purchase won't be allowed. Adobe is the only large company in the industry and Figma is the closest thing they have to real competition.
Miro is better. I have enterprise licenses for a million of these damn things, and Figma’s licensing / sharing is one of the worst. Guests can only edit for 24 hours, and you have to renew edit access every day unless you give them a paid seat.
Miro also has a slightly more robust feature set, also has lots of fun things in it, and is also fast.
Figma likes to enable free shit, not allow admins to restrict its spread, let an org adopt it, then start charging. Really shady business practice.
To each their own, I really don't like Miro as is just graphical, no way to export my data in a machine readable format. In LucidChart I could create an ERD diagram or BPMN chart and get it in say XML in a format that I could actually script on top of to help with development. As for direct Figma competitors, I've really enjoyed self-hosting PenPot
I think it kind of depends on what you’re using it for. Lucid started with diagraming as their primary use case. Miro was created to be a more performant version of Mural, and was focused on remote affinity mapping and white-boarding.
That's why Google announces the end of things unlike other companies who will just silently let them fall into obscurity. They don't want to mislead people