Yes, the ‘BCSB’ plugin is easy to use. Just install, activate, and bot comments are blocked. No settings to worry about, it just works.
(I installed it on one site that was getting bot comments, and BCSB just stopped them immediately. And bot comment submissions don’t even get to the database, which other plugins allow. So, bot comments don’t impact the database.)
As to why more people don’t use it – it’s a visibility thing. If you search for “spam” in the Add Plugins screen, you’ll find lots of choices, with BCSB farther down the list – because it’s not as popular as the ones that (IMHO) don’t work as well.
Chicken/egg thing: more installs, more visibility, but not very many installs, less visibility, so less installs. More installs, more positive reviews would help.
(It’s the same thing with self-published books. Marketing to get buyers/readers is hard. You might have an excellent book, but if it doesn’t show up on the first few pages of a book list, then you don’t get very many sales. Other than the ‘friends and family’ buyers. Reviews are important to help make your book more visible. But less than 10% of readers actually write a review. Probably the same with plugin reviews. )
Glad the update fixed things for you, and it is working well. Thanks for the positive notes and review.
As for suggestions – always open to them. You can make them here, or via the (bot-protected) comment form on my author web site – https://www.RichardHellewell.com .