We use Slack but strive to be responsible about it. We've worked upstream to write better issues using issue templates, leverage conversations on GitLab comments to these issues, Wiki, etc. We put a lot of effort to let people focus. I even told the team it's better to disable notifications, and told them explicitly I don't expect and answer right away, and that if I do or they do, that would be the exception rather than the rule. When these exceptions occur, we treat the incident, and then dig to find the root cause that made it necessary to tap on someone's shoulder, and then we fix those to avoid that in the future. Writing better docs, adding sections to issue templates, recovery mechanisms, code, etc. This is valid for everything, even payroll or taxes where someone had to call me to fix something and we instaured things not to have that emergency come again.
We do everything possible to safeguard people's focus. Then when we do calls, we have a collaborative notebook (right in the platform we're building) we can live edit where we put the agenda beforehand. People add things they want to talk about.
During the call, we can add points and remarks, answer the questions, and write proof of concept code right into that executable notebook.
We're at a point where people look forward to calls. It's a balance.
No productivity tool matters if people don't let other people produce something in the first place.