Might be biased since I'm a cap sun with cap ascendant (and frankly 4 other planets in cap, yes they all conjunct each other), but Scorps are far from being the most problematic people I've had to deal with, and I had to deal with a lot.
Mean guide for mean people: if you want to break someone, first win their trust and then betray them. Scorps will internalise the lesson and tell themselves "That's what I get for trusting people with this and that character traits/background". Or just make fun of something they do not have/they suffered for in the past.
I think it's more about Mercury and other placements influencing one's mental attitude/capacity. The most annoying ones to deal with for me are fixated minds, who once they hit a certain age simply become close-minded, accepting only what has worked for them until that point in life and what they grew accustomed to. Which pretty much comprises a big part of the population.
It's futile to try and explain someone rationally that the x or y tendency is harmful and shouldn't be tolerated if they grew up being scolded to do it or have been made fun of for not doing it. Example: it's extremely hard to try to modify someone's reaction and thinking once they hit their 30s (not to even mention when they're in their teens, unless you rip them out of their environment) and got used to seeing around them things such as: sexual assaults/offences and misogynistic behaviour, curses, corporal punishment... (again I might be biased, but males are more inclined towards these things due to some weird cultural tendencies in certain countries).
Oh, try convincing people that grew up in alcoholic entourages that they should give up smoking/drinking in social situations. Most will get pretty bad anxiety if they can't bottle up their thoughts and feelings with alcohol and smoke. Oh but that and STDs are perfectly normal... meanwhile, saying things such as "I am trying to become a better person by understanding the philosophical and spiritual lessons behind different astrological systems and also the world around me" is mostly a prohibited thing to say in a world where "common sense" is in fact pretty rare. Kinda how you are required to say at the start of every sentence now "without being condemning of one's view's and by trying to make it objectified and without being racist and also #nohomo but it's not like I have anything against them really without offending anyone" because people literally can't tell the difference anymore unless you state it out loud, and even if it's a lie and you really are a "racist prick", they'll believe it anyways because you stated it. I'd love an astrological interpretation of the above happenings.
Try re-educating a kid who has been told for years of their life that they are ugly, stupid or have a disability (that's not an actual disability and could have been treated).
For me, Scorpios can be really receptive and sensitive, despite how some learn to toughen up, it's exactly because of the receptivity that remains and how they can perceive the people around them. If you chose the calm, clear way of showing someone who you are and your point of view, that is going to be better in the long run for all the parties involved rather than a fiery verbal burst and ego clash, but good luck refining that without reserving a lot of time for yourself. And watch out for that little stingy thing.
I also think the positive Saggi influence can help.