Google and co will essentially pay for the SLA, free access will be available through Wikimedia Cloud Services and I'm sure that the team is investigating how to make the API available to the wider public.
Devils advocate: Google clearly already has a working pipeline to import and format Wikipedia data for its needs. Why would they stop using it and start paying Wikipedia? Will Wikipedia be able to build an enterprise API thats faster/cheaper/more reliable/more scalable than the internal one build by one of the world’s top engineering companies?
No doubt the enterprise API will add attractive value for smaller companies without the resources to process the raw dumps but I’m skeptical that this will convert Google et al into well-paying customers. Unless they start restricting the free dumps...
While Google already have a pipeline in place the bottleneck of that pipeline is on the Wikimedia end of things, this project addresses that. No more scraping and data dumps when they can stream changes over gRPC. WMF didn't build this without consultation with these big companies.
No doubt the enterprise API will add attractive value for smaller companies without the resources to process the raw dumps but I’m skeptical that this will convert Google et al into well-paying customers. Unless they start restricting the free dumps...