Working at an established org right now, where the team is still remote first. I tried suggesting this, but got pushback and the team actually settled on the opposite. For example, they want any optional changes (e.g. suggestions) in pull requests not to be left as comments but discussed in private which 90% of the time means calls. They seem to dislike discussion threads in Slack and want meetings for things instead. I’ve also noticed things like the person who reviews a pull request being the one who has to merge it and essentially take responsibility for it, versus just giving approval and the author merging it and making sure everything is okay after CD.
I’m very much the opposite and prefer to have things in writing and like asynchronous communication. But when it is written messages, usually people either ask for a call or just do “Hey.” I actually made this a while ago hah: https://quick-answers.kronis.dev Either way, people also really seem to dislike writing README files, or all that many code comments, or making the occasional onboarding script or introducing tooling to do some things automatically. I don't get it.
What you have is people using a tool for different objectives, and when their chosen behavior hinders your objectives things seem out of whack.
I'm against shoving an eye of sauron communication hose down people's throats. I simply give my constructive feedback after the fact. E.g. when someone dm's me I say, "so-so is waiting for this to be done for their thing, so mention this part in the channel." or "the other team would need to know this for a refactor, so add this info to the wiki." If someone feels the need for dm'ing for some psychological safety so be it. But the cost of that safety is additional communication overhead for filling in gaps that the person should be ok with. And the people that value the psychological safety they gain usually don't object or have no grounds to object to a duplication of communication to fill those gaps when someone points out those gaps exists.
Realistically, if the team decides that synchronous communication and not keeping too much of a historic record works best for them then I guess that's it, it's up to them to deal with that long term, since I'm just a colleague and it'd be counterproductive to try and change everyone's mind. If I did something like that, I'd probably just come across as a bit of a jerk.
You can show people the benefits of a particular approach but whether they accept that those are benefits (e.g. looking at a pull request of mine from 2-5 years ago that shows context for why a certain change was done a particular way, has images of benchmarks, descriptions of other factors to consider etc.) is up to them. Same for synchronous communication: to them, being able to call someone and have a conversation might be easier and more productive than the alternatives, they might just be unbothered by context switching or interruptions... somehow.
Though one could probably argue that some practices (like version control and CI/CD, for example) are objectively good to have, regardless of personal preference, for the sake of the development landscape not looking like The Wild West. How far that might extend, however, I have no idea.