Sorry, I did not see your comment until now. Unfortunately, for whatever reason, Industry areas do not seem to function with District Style. I made a District Style for this Collection and for Simple farming and published both, then tested them, then found that they did not work at all to control what spawned in the Industry area - it only obeyed the assignment of generic industry, forestry, farming, mining or oil and did not conform to the District Style. So, I went back and deleted the Simple Forestry District Style and I was about to delete Simple Farming District Style but already dozens of people had subbed to it, so instead I put a comment on it to disclose that it did not work as intended.

Thankfully, specialized industry only has one level, so it is very easy to just control what grows there and delete any modern buildings that grow until it is full of these Simple Forestry assets. You do not even have to make them historical because they will never level-up, and another benefit of that is if they ever do become abandoned you can bulldoze them without worry, since they aren't historical or high-level.

Thanks for the response and explanation