Only people under heavy Non Disclosure Agreement could assert that any of the competiting company is leading/behind in terms of R&D. An no such people would be foolish enough to comment about that publicly. Big money and strategic informations are at stack.
Conversely if any company brag about it’s leading mastery without delivering this should be considered as a PR stunt until proven otherwise.
No.
So by definition Apple can’t be behind of nothing.
*Tesla "autopilot" which require all time human supervision clearly doesn’t count as of now.