Your review is an entertaining read, so thank you for that. Unfortunately you’ve based your opinion on some incorrect assumptions, and the angry / aggressive tone is a dead giveaway of this. In case you’re interested, I can provide some more information to correct some of those assumptions.
The WPSSO RRSSB add-on offers a settings page where you can choose the post type(s) on which the buttons will appear by default, and the location within those pages. For example, it could be only on Posts + the content block, so buttons would not appear on Pages or custom post types like Products, Events, etc., and not in excerpts, the sidebar, or admin editing pages. Post types and locations are easily selectable in the WPSSO RRSSB settings page. If buttons are selected to show only on Posts, and they also show on other webpages that are not (supposed to be) Posts, then those other pages were probably created by a plugin that doesn’t use WordPress post types (the default WordPress post object is “Post”, and anything else, like WordPress Pages are custom post types). If a plugin creates non-standard webpages without defining a post type, then there’s nothing other plugin authors can do about that – they would need to fix their plugin to use proper WordPress post types, if they don’t want their webpage to be Posts by default – that’s just how WordPress works.
As you’ve incorrectly stated, the WPSSO RRSSB add-on can (and does by default) add share buttons to the WordPress editing page. Authors often find this very useful when they are finished writing their content, so they can share it directly from the editing page, instead of going to the front-end page and sharing it there. I don’t know why you would believe that the share buttons would share the editing page URL instead of the front-end webpage URL (aka the “canonical URL”). And certainly that would be easy to check just by clicking a share button.
You’ve stated that you don’t know why a Schema plugin would be necessary for a sharing plugin, which means that you are not aware that social sites read meta tags and Schema markup from the webpage URL being shared. Correct and complete meta tags and Schema markup are essential to provide social crawlers with the correct information about the webpage URL being shared (ie. title, description, image, etc.). The WPSSO Core plugin is required so it can provide meta tags for Facebook and Twitter along with extra markup in the content for Pinterest (not to mention LinkedIn, WhatsApp and others). Adding share buttons to a webpage without that webpage having complete and correct meta tags and Schema markup is possible, but definitely not desirable, as social crawlers would then choose any random image or text it finds on the webpage – I can’t think of any site owner that would actually desire this.
Hopefully this has been helpful in correcting some of your assumptions.
js.