This is just my opinion, but I think it's just the sheer number of vessels that are trying to get into Vancouver at once. They simply don't have the resources to service them all.
Even if there may be a pier available, they need to have harbour pilots, tug boats, etc., not to mention Customs agents to process the import manifests. And piling too many boats outside the strait just results in clogged waterways and limited room for the ships that
are getting in and out.
@604_Dialect works at the port and thinks that MM will be serviced later this week. I would expect to see her start moving anytime between tomorrow and Monday - but even once she does, it'll be a slow 15 knot journey into the strait, clearing Customs, and then meandering over to Fraser Wharves or Annacis (the former is my guess).
And then
@Bob123 is going to commit to not drive his new shiny Tesla and watch the webcams 24x7 for more car carrier trucks all week out of solidarity for his fellow brethren!
Right Bob? Bob?