It has been interesting to read along here, as I used to blog in a previous life and made some small amounts of money--and still do get checks here and there from those blogs even though I think the last post I published was approximately 4+ years ago. I did look back through some of the archives to try and refresh, or confirm, my memory and thought that I would share a brief summary.
I launched my first blog, which was about my desire to FIRE, back in August 2006. A little over 6 months after starting that blog, I had created a personal blog that was intended to track my efforts of earning income from blogging and the first financial report I published was in March 2007 when my blogging had earned me $116.70 that month. I haven't checked all of the monthly reports but a lot were in that range in 2007, and then in 2008 I was earning the most that I ever earned from my blogs with the record month being $762.26. The earnings were predominantly made up of advertising--using things like AdSense, Kontera, LinkWorth and TextLinkAds as well as private ad sales that I had brokered with other site owners (these were more prevalent in the 2008 time period when my blog was earning $500-700 per month. I did get into some sponsored posts and created some additional sites that were completely driven on affiliate links to Amazon, or using services like Datafeedr to pull in products from companies that I was an affiliate. I never really did well with the affiliate sales, partly because the commissions were small and my traffic numbers were never huge.
On the highest month I mentioned, here are a few examples of my income sources: AdSense $89.76; TextLinkAds $276.53; LinkWorth $145.71; Private Ads $159; Affiliate Links $62.96.
As I mentioned, to this day I still receive checks here and there that add up to about $1000-1500 per year. There are some affiliate checks, for services such as Aweber, and still some advertising money. The other one, oddly enough is AdSense that can usually earn me $30-40 per month--which isn't too bad when you remember that I haven't actively written anything in about 4+ years.
You also have to keep in mind that a lot of bloggers report on their earnings, but not their profit. I noticed that the blog that some have questioned here did provide some information there regarding the expenses. However, I recall when I was actively blogging that there were plenty of sites that would highlight they earned $50,000 that month (purely an example) but didn't mention that they also spent $47,000 on advertising, etc. I am sure there was still good money being made but the ridiculous amounts could easily be misleading.
Of course that led to a lot of "here buy the course I created to show you how I made x per month", and that is still there today even in non-blogging things that I have dabbled in, such as selling physical goods on Amazon via FBA.
Keep in mind that making money from a blog doesn't always mean you are only making money from the actual blog. As an example, I had taken nuggets from what I was writing on a few of my blogs and self-published Kindle books. That then became another source of income that could be advertised to new readers on the blog. For some, that can then lead to speaking engagements or other offline deals. The blog can be a springboard to many other opportunities.
With all of that said, I did stop actively blogging because I found that doing that on top of my FT job was sacrificing too much time with my family and putting a good deal of stress on my relationships. I haven't been able to completely give up on those entrepreneurial dreams (as I mentioned the FBA, Merch, etc. that I still dabble) and I love the behind the scenes stuff with setting up blogs, and maybe someday will get back to writing as I did enjoy the process.
I don't know if any of the above will be useful or interesting to anyone, but I thought I would share my experiences from about 10 years ago now to show what someone that didn't really know what they were doing at the time could do. =)