Fair points. I used to think that until some months ago but the latest generation of OSS models are surprisingly good. Plus maybe it is the way I work, but I find myself constantly overriding the decisions of frontier LLMs (because they start degenerating towards god objects and spaghettification) so most use I have gotten out of the AI agents is really their ability to code quickly and syntactically correctly.

Also worth noting that it doesn't have to be full either-or, there can be a two tier enterprise deployment that routes to locally hosted vs frontier model, over time more and more usecases could get routed to local LLM