I think part of the problem is that what we think of as "intelligence" is a vector quantity and can't be well described by a scalar like IQ. You can define some metric on the vector intelligence, but that metric will be arbitrary. You can think of "intelligence" as a combination of memory, quick-thinking, spatial visualization, abstract mathematical ability, social abilities, etc etc. What combination of those are important will be different depending on what activity you are doing.
The particular problem here is that most people want intelligent companions in order to have interesting conversations. I don't think the standard IQ measurement is a good indicator of how interesting someone is to talk to.
I think most people just naturally find others with compatible ways of thinking. So using IQ to find companions who are also looking for high IQs may be pre-selecting for people who are not very good at socializing. Its not that high IQ makes you bad at socializing, but rather that if you are good at socializing, you won't need to use IQ to pre-select.