Where there is just one example, we don’t need a comma?

If there is only one example, there must not be a comma in front of such as?

I have seen this one, We can use such as to introduce an example or examples of something we mention. We normally use a comma before such as when we present a list of examples. Where there is just one example, we don’t need a comma:

https://dictionary.cambridge.org/ko/%EB%AC%B8%EB%B2%95/%EC%98%81%EA%B5%AD%EC%8B%9D-%EB%AC%B8%EB%B2%95/such-as

Do you agree with this?

Or whether there is one example or some examples, if the information of the example(s) is essential, there must not be a comma before such as and if the information is addtional, there must be a comma in front of such as?

What do you native native English speakers think? And if you don't mind, could you give me some examples?

Thank you so much as usual.