Thanks for pointing this out. It is not properly explained on that page, and besides I've learned a lot since I wrote that. I will correct it.
First you cannot damage your site trough links according to the most recognized experts for the reasons you mentioned. All you can do is get zero value from those links. What can happen is you get value from the links, then one day G sees what is going on and you don't get value. Your ranking drops from page 1 to page X.
There is a social media slap according to some experts and this is what the paragraph in question is referring to. If ALL your links are from SM sites, G will discount them heavily, but I no longer believe that it will get you sandboxed. I did get a site deindexed after two weeks of page 1, and all the links were from SM sites. I may never know why.
Finally, what I am trying to get across is that natural is better. The more natural your link building appears, more unique text, more unique sm accounts lots of non-sm links, natural link velocity etc etc the better it is. TLJ does its best to enforce this by limiting the daily links per url and encouraging proper use of spyntax. Still some users get it and some don't. Again, thanks for your input.