There are different communities for answers like that, for general techsupport. Maybe OP asked it in a wrong place, but if it’s already here, and does not sound blatantly oftopic it should be answered in the spirit of the community.
And the answer was also wrong, OP asked how to save as inverted, not how to open inverted.
Yepp, Hanlon’s razor: they are mostly just lazy and maybe incompetent, not necessarily evil, that’s just a side effect. E.g. in my country if you call them that you want to get out of CGNAT they’ll just do that for you. My IP haven’t changed in years, but I don’t pay for fix IP. But it may be different in each country, I have mostly good experiences with local ISPs here.