Are the days of using dashes over? [duplicate]

I ran into a sentence which I would like to share in here to prepare the context for my question.

"it was shown that TBT, HBT, and HSDT1 have the same results in order to derive fundamental frequency of the nanobeam – ABT and EBT are the same as well – in all of the different selected aspect ratios and gradient index parameters."

Now, I need to know if the two dashes used in this sentence represent what grammar calls 'parenthetical phrase'! Plus, I guess using dashes in sentences has become a bit of tradition and commas are good replacements for them. Correct me if I am wrong.

Yes, the two dashes in the sentence represent "parenthetical phrase" or you can simply say that the dashes set apart any extra information relevant to that particular sentence. The dashes can be replaced by the commas (parenthetical commas). I won't say the use of dashes for this purpose is diminished. Based on what I come across (in medical and healthcare-related texts), I frequently see dashes used as "parenthetical commas". The usage is not wrong.