Others having the same problem? Yes, several discussions running here about the same problem with lots of advice offered. Some just a bit further down the page. :)

Assuming it isn't slugs and given all the garden pests you have listed then likely some sort of fencing will be needed. Otherwise there are many brands of spray-on mammal repellents you can try that will usually work for periods of time if you keep applying them.

But the key is to first ID exactly what is doing the damage by observation. Then you'll know what specific prevention is needed.

Dave

Here is a link that might be useful: Eating leaves discussions

Look for a little green worm on the underside of leaves. Cabbage worms I believe. They get me every year too.

Yes, the cabbage white butterfly had been laying eggs on my kale like crazy. Every time i look, there are fresh eggs. The caterpillar is green and camouflages well. Here is a big guy that I didn't notice until this plant has been almost completely eaten. Do you notice any of those small white butterflies around? If so, I bet that's what it is.

Among vertebrate pests, rabbits are the most likely culprits where strong-tasting brassicas are involved. Deer, coons and rodents don't particularly like them unless there's nothing else to eat.