Choosing Between `Context.Tag` and `Effect.Service` for Services

Should I be using

.. extends Context.Tag

.. extends Context.Tag

syntax or

extends Effect.Service

extends Effect.Service

syntax for services? I have been using

context.tag

context.tag

however, this course (https://www.typeonce.dev/course/effect-beginners-complete-getting-started/layers/effect-service-service-and-layer-all-in-one) as well as in the effect 4.0 talk by michael seemed to suggest we are moving towards only using effect.service. Would appreciate any advice! thanks