for my own sanity i will assume the audience of that page you linked is business customers given one of their examples is a .gov. im just residential. getting a static ip out here felt monumental in itself

it was apparently impossible for my isp. i have a very good deal on a static ip so reluctant to rock the boat

even if you get port 25 unblocked your IP won’t pass the sniff test. you must have a PTR record on the IP pointing to your domain for the large email hosts to accept mail from you. i use amazon SES to handle outbound because of this hurdle. it sucks