Not enormously. The biggest difference is Hasuras console, which Postgraphile lacks. However I don't really see that as an advantage in favour of Hasura, postgraphile + graphile-worker + graphile-migrate (all by the same author) has worked so much better for me than Hasura.
One thing is that it's open source, not proprietary. You can run it on your own servers, modify it, etc, for free.
Another thing is it's Node, and can be used as a plug-in to your express app. This can make it easier to customize and extend over time. Eg; have parts of your schema be postgraphile and parts be custom JS.
My apologies! I'm not sure why I misremembered that. Perhaps I was confusing it with Prisma... Which appears to be open-source as well now. Hmm, my mind must be playing tricks on me.
Biggest difference I think is that Hasura doesn't use RLS for security. It has it's own privileges/roles implementation. Postgraphile kinda works in postgresql, hasura works with postgresql.