Very similar, yes.
Except that Kay did not envision the distinct computers communicating via REST.
https://blog.metaobject.com/2019/11/what-alan-kay-got-wrong-...
Also: microservices currently require at least process and frequently even VM/Container/Machine boundaries.
In-Process REST scales that down:
https://link.springer.com/chapter/10.1007/978-1-4614-9299-3_...
Language support for In-Process REST: