Transport, comms, banking, and information technology, tend toward monopolies.
Consulting is a mixed bag -- if you're relying on creativity, not so much, but if you're relying on marketing and business contacts, both of which are far more a network effect (with strong lock-in elements), yes. Contrast your typical small-gig design shop vs. the Big Declining n Accounting Firms, or IBM and Oracle (consulting / business services).
Retail can be local (small effects) or global: large grocery stores, WalMart, Amazon.
There are other effects as well. I've been curious about Maersk's adoption of ultra-large cargo ships, even as shipping volumes have been falling. While there's a financing-design-build lag, there's also the possiblity that having and operating a large ship puts pressures on other operators -- if you're operating and loading, you're taking cargo which would go onto smaller vessels.
It's complicated.
Part of this also plays into concepts of what and how technological mechanisms actuall function: https://ello.co/dredmorbius/post/klsjjjzzl9plqxz-ms8nww
I'd include among "network effects" urban and even empirical structures.
There are industries which tend naturally toward monopolies, with transport, communications, broadcast, and software among them. There are also industries which tend naturally away from monopolies, such as sandwich shops, cement providers, and laundromats.
(Not that there cannot be some concentration, or even national chains among these. But they're rarely dominant.)