When I first started, data was posted to the genweb sites, the boards were for queries. I have found a lot of information and made major connections on the message boards, and I have also helped countless other people through answering their queries. I have also found fascinating history about where I grew up through answering others queries. A lot of people today know nothing of doing genealogy research, partly due to the "dumbification" of Ancestry. They have no idea of how to find information, other than from Ancestry. If I want an obit, I am not going to go to the boards first, I am going to google the name, or check the local newspaper or library for archives.
You are right, many people do not know how to write a good query.
I stand by my opinion - frequent constant obit posting just clutters up the boards, and is not their purpose.