basically for android box. it is recommended that the spec should have atleast a 16 gb storage a 2 gb ram 4 gb ram recommended. As for processing technically for streaming it does not need much cpu a device with gpu processing will enhance the viewing experience. Another issue need attention is the os compatibility that will need those that have experience using to commend. other than the technical spec what software support they provide but usually not very dependable. maybe work well for a start after that most will fail.
the best android tv box - nvidia shield - has only 3GB. This box is powerful enough for some serious games.
In 2019, nvidia came out with another version, only 2GB RAM, for those who want to watch TV, not playing games.
Most of the good box based on android TV OS, are using 2GB/8GB. 2GB is sufficient for playing video and some light games.
even with 2GB, most of the time, there is about 1.1 GB free RAM available to run apps.
For watching TV, it is better to use boxes with android tv OS.
Those boxes that run on handphone/mobile android OS need more RAM, because they are running lots of redundant processes behind which are meant for handphone.