Another point of view:

https://www.merriam-webster.com/words-at-play/the-many-plura...

Octopi, octopuses, and octipodes have all been used. I personally think octopi rolls more smoothly off the tongue than either of the other two, so that's what I tend to use.

I find the arguments regarding Greek or Latin purity to be unconvincing- we are speaking neither language. We're speaking English, which is a head-on collision between the two, with Germanic trappings gluing it all together. I happily mix and mash whatever prefix, root, infix or suffix I like. If others like it and use it, success! Whether a theoretical Roman from centuries past would agree does not enter the calculation.

Your argument is that all words are made up?

You could say this about any language and of course, it still holds true.

No. My argument is that applying rules from other languages as if we are speaking them, and not English, should not hold sway. Rather, we should pay attention to sound and flow in English when deciding how to pluralize, etc.

Whichever one you use, most people will understand you, so ultimately it doesn’t matter. English is full of loan words and they’re often used in different ways than their source languages. There isn’t a settled plural in English, though many people have strong opinions about one or another being right.

No need to apologize. I used "octopi" because that's what my father always said. I have no opinion on the matter.

Interestingly enough, octopus has multiple pluralizations, the other being octopodes