You must have a a very nice climate or micro climate in your garden Eric, being able to grow so many non-native plants!
Yes we do upset nature quite a bit. Snails, worms, aphids, ants, caterpillars, beetles etc etc.
In return we do give the bees a source of nectar, and grow plants to attract butterflies, flies, etc etc.
The number of gardeners appears to be dwindling in this day and age, I suspect, so maybe nature will have a chance to recover
I know it doesn't take my garden to revert to nature!! Weeding is a continual battle. Personally I find it therapeutic, as my son described it on his one and only weeding session when we went a-gardening. I just wish there wasn't so much of it!