Why is the simple past form "did" used here? In other words, is it still clear, grammatical and idiomatic if present simple tense is used?

It sounds like the tutorial is saying (link with a time stamp corresponds the following)

if you did like this video give it a thumbs up

I guess the reason that the presenter uses "did like" is to emphasize "like".

The quesiton is,

Why is the simple past form "did" an appropriate tense here?

In other words, is it still clear, grammatical and idiomatic if present simple tense is used?

if you do like this video give it a thumbs up

or simply

if you like this video give it a thumbs up