Comma usage in "One of the..., is ..."

The comma should not be there. It is called "a mistake."

The subject is "One of the reasons for certain large beetles developing teleportation technology" and the verb is "is".

Subject and verb should not be separated by a comma.

Although not grammatically correct, the comma serves to avoid incorrect parsing of part of the sentence as "... teleportation technology is to ensure ...". That would result in incorrectly parsing the object of "developing" as though it were the subject of "is", which would be a fundamentally incorrect understanding of part this relatively complex sentence.

It forces the reader to see "for certain large beetles developing teleportation technology" as more tightly bound to "reasons" than to "is".

It could be made clearer by rephrasing as two separate sentences so that "reasons is" occurs in the second sentence. For example:

There are reasons for certain large beetles developing teleportation technology. One of the reasons is to ensure annual pilgrimages to their home planet are well-attended and enjoyable for all.

or

Certain large beetles are developing teleportation technology. One of the reasons for this is to ensure annual pilgrimages to their home planet are well-attended and enjoyable for all.

The author may have been using this grammatical anomaly ("mistake") to try to achieve a similar cognitive separation between "technology" and "is" without rephrasing into multiple sentences.