Lectins affect some people more than others. I'm eating low lectin and low oxalate and quite a few foods have high levels of both.

You're right about potatoes. Years ago we always peeled them and boiled them to mushy and tipped the water off which removed a lot of the lectins. I was eating tomatoes but removing the seeds where most of the lectins are, but it got too fiddly so now I don't eat them. When I drank years ago I had to avoid red wine which gave me a headache, blocked nose and bright red face, likely from the sulphites and higher histamines in it. As you say, what works for one person doesn't for another.