One of the most annoying things when putting together a demo is the glue code to other systems.

Writing your own error-prone connector logic to other services you're drawing from.

An ecosystem where someone else has likely written the logic, and you can rely on it indirectly, will be more fun to experiment in.

More work will go into duct-taping existing components together into novel combinations.

Less work will go into users writing the bill ball of duct-tape to be the glue-code to another system.