To be fair, Boring's other projects will likely have purpose built vehicles. Boring has submitted proposals for other tunnel systems which would require 12 or 16 person pods (presumably built by Tesla). But AFAIK Boring hasn't won any of these contracts yet. Again AFAIK, The Vegas convention center loop is the only contracted project so far. Note there is negotiation underway to extend this loop to the airport and the entire strip - at that point, luggage comes into play, etc.
I gotta say, picking between all of Elon's companies to invest in, Boring would be a very attractive investment indeed.
Edit: Just to give you perspective. Boring won this three person station contract with a $55M bid. A giant German company known for ski lifts among many other things, put in a bid for $500M. That's what you call disruption.