If force sensitivity is a recessive trait, it would be possible to be force sensitive but not have force sensitive parents and vice versa.
If force sensitivity was a recessive trait, all kids of two Jedi would have this ability, too. And kids of non-Jedi would have an incredibly small chance to be force sensitive. This would make it almost mandatory that Jedi have families and children, otherwise the order quickly runs out of members. It would make more sense if Anakin’s romance with Padme was prohibited because she’s not force sensitive.
Now on the other hand, if force sensitivity would be dominant, everyone with a Jedi in their bloodline would be force sensitive. And what does the Jedi order do? They track down Jedi familiy trees, make them join the order and prohibit them from having children on their own. So in this scenario, the goal of the Jedi order is that the gene for force sensitivity dies out.