If they exist there are two reasons aliens haven’t visited earth. Either they haven’t discovered us or they simply aren’t interested in us. Of the two I think a lack of interest is preferable. It means they’ve discovered us and decided we weren’t worth bothering with. If they haven’t discovered us we should hope they don’t and if they do we should hope they pass us by.
The problem is that the bad reasons they might contact us are far more numerous than the good reasons they might contact us. The only good reason would be that they’re friendly and want to be friendly with us for some inexplicable reason. If they were here seeking resources it would be a very bad day for us indeed. There would be little point in strip mining the planet, sucking up our atmosphere, or draining the oceans. All the things that make up the earth can be found in vast abundance all across the universe. The biological proteins are the only thing that appears to be rare in the universe.
Aren't you contradicting yourself?