I empathise to a point OP, I can be very direct but I have found that has enhanced me professionally. In fact, and I am a consultant too, I have had work specifically because I am very clear in what I say and do.
However I do believe the reason I am palatable is a lesson I was taught when I moved from one sector to another.
I got a very tightly timed and delivered dressing down in earlier days where I frustratedly pointed put that someone was wrong in what they did. The response I got was about choice and capacity. The person challenged me and said (I'm paraphrasing)
Ok , so they are wrong , they will get a negative consequence to their action. Fine , you have warned them of this , no why do you feel it is acceptable to try to take that choice from them?
I sort of stuttered and they carried on
It is not your right to stop someone making a wrong choice. A dangerous one...yes ok (this is elderly dementia work) but how dare you treat them as of they can't choose to learn from the consequences of their actions. You need to treat people as equals and that includes accepting it is their choice to make mistakes.
I was floored because they were right, this incident was over someone early dementia. They had full capacity, I was technically right but by insisting and being so forceful I infantilised them because I wouldn't accept that they had the right to make that choice.
It ultimately comes down to you wanting to control their actions, you say you feel passionate about not wanting them to do things wrong. You don't get to choose that. You can give information and your advice but by insisting you just want to help them be right or do x , y and a, what you actually are doing is saying , I'm better than you so I will take your choice away. Yes that will put the client off, as it should.
I'm an adult, it may be you advise me something but I choose to take the consequence of a different decision for reasons you have no idea. Patronising me or pushing it ? Yes I would not be using you again.
It's about considering respect for the other persons choices.
Until I got pulled up on it I would be like you, but I now , I am still direct. I give the options and I warn clearly of what consequences may occur but if the client chooses to continue that's their choice , and I mean it when I say it.
I found with my partner too, hes not a child , he has the right to make his own mistakes, it's not for me to decide what is right. I'll give my opinion and respect his choice
So honestly OP if you start seeing people as other adults able to make their own choices , it wont be about being direct or blunt , it will be about respecting others choice.
You can feel as right as you like about your views. However they are just that, your views. Allow others to make their own choices.
I'm not sure this is being blunt, as I say, I am blunt but it doesn't affect , more enhances my career. This is about being controlling and overstepping. When you change that I suspect you will se a change (and I say that as a mostly reformed control freak)