Wow you didn't hardly read that at all did you?
...and I'm not the person that you replied to before.
To be fair, your question was awkwardly written.
It's also not exactly a 'fair' question. SEER ratings take into account ALL of the electricity used in operating the unit. This includes both the condensing unit as well as the evaporator unit. As you likely know, mini-splits are meant for point load cooling, a single room/area. Standard packaged rooftop units are typically ducted out. Because of that, their supply fans are quite a bit more powerful (IE, use more electricity) because they have to overcome a lot more static pressure, both internal and external. Even the lightest duty 2 ton packaged unit is going to be able to flow a nominal 400 cfm/ton at ~0.5" of external static. Even the ducted versions of mini-splits cannot meet that. They typically are designed around a much lower cfm/ton number, and then can barely deal with 0.4" of external static.
Combined with the lack of accessories they can be provided with, like various filter options, economizers, outside air dampers, powered exhaust, etc, etc, etc.... they are just limited in terms of applications.
And as far as heat... you're right, sorta. Traditional packaged heat pumps operate with a 'normal' heat pump, meaning you're stuck with COP's hovering around 2 when you get down to 17 degrees, meaning ~50-60% nominal heating load. At that point, if additional heat is required, you typically make up for that with strip heaters, or a dual fuel setup. On the flip side, packaged units can be provided with both direct and indirect fired gas heaters. And that gives you even more freedom to do what you need to do.