Don't think my neighbours believe in anything.
I'm involved in various Christian activities locally. The trinity is something I simply never raise or discuss with any of them.
Interestingly, my Mum has recently decided for various reasons to become an Adherent (=decided to join/become a member) in the Salvation Army. The joining form requires applicants to affirm their belief in the trinity. She declined to sign this and asked the membership sec to come and see her to discuss, and raise with his/her superiors. In between times, however, the form has changed and now requires wannabes to simply affirm they hold to SA beliefs, with none spelled out specifically. She doesn't mind signing this.
I applied for a job recently (which I didn't get) with a Christian organisation. That application required a declaration that I agreed with their beliefs, first of which was the existence of the trinity. I pondered this and did sign the declaration, because I figured that the work done would exceed the lie (that they believe!) but I had and still have qualms about that.
I've always thought that if the trinity doctrine was important to God and the Lord Jesus, they would have done something about this lie before, in the hundreds of years since it was first promulgated. As they haven't I conclude it can't be that worrying to them and there are bigger issues that they concern themselves with.