I suppose that reporting does happen or at least could be made to happen under the new system. I used to make $80k per year in salary(which is far less than mo

I suppose that reporting does happen or at least could be made to happen under the new system. I used to make $80k per year in salary(which is far less than most of the top decile in the USA) and in one of those years had over $10k in capital gains. In the same year I thought about buying a house to rent out. I ultimately didn't do it, but if I had, then I would have had to declare the income as part of my tax return filing process. Just as one data point.