Re: why matchmaking take so long

First, there are not millions concurrently playing on your data center.  Second, your rank is platinum, which is only about 17% of the player base, with less than 2% above you.  Both of these factors will weigh heavily on your queue time.  If the queue was rushed, you would have complaints about bad matchmaking instead.

Have you played Overwatch?  Ranked queues can easily be longer than 10 minutes.