Is there any statistics on that? This might be an explanation for dumb patents. I am seeing quite a few of those as I am searching through google. The application process isn't expensive unless a lawyer is involved. Hence, without the deterrence of high price the number of bad patents increases. This is my theory.
There is an article in PatentlyO with statistics about the success statistics in various categories. It says only 1% of non-provisonal utility patents are filed pro se from a limited sample. That doesn’t explain a large number of “dumb” patents. However, if an independent inventor with a dumb idea hires a professional to help they might still end up with a well written but dumb patent application.
From the PatentlyO blog -
The most surprising result: Overall in this sample, I found that over 99% of patent applicants were represented by a US patent practitioner. An important note here is that the focus of this study was non-provisional utility application filings. I expect that the rate of true pro-se applications would be much greater if we looked at provisional patent applications.
It has a table with success rates -
Another article took in a much bigger sample and was more rigorous. I do not see that it address your question, but focuses on success of those that are filed. The Lone Inventor: Low Success Rates and Common Errors Associated with Pro-Se Patent Applications It also examines differences in content of applications between represented and non-represented applicants.
I will note that represented means a registered practitioner which can be as attorney or not an attorney (a patent agent).