> GitHub/Gitlab as a service easily saves more than 5hrs a week.

> I have custom slack bots that easily save me a couple hours a week in aggregate.

> Then there’s services such as managed CI or, heck even things like the “search” function on a wiki, those are all things that can be provided by a service.

These are three highly subjective, very unconvincing statements. I use Github, Gitlab, multiple slackbots (some I wrote, some others wrote), managed CI, and a few search services internally in my company every day. I have no confidence that any of them are timesavers in the way that you state.

Slackbots in particular have been shown to use more time than they save (context switching is extremely costly). Github is a source-code host that ads distracting social features, notification queues, etc. all which can add to an employees distraction load and decrease productivity when compared to a more basic code-host.

I'm not saying they don't save time in aggregate, but there's certainly arguments on either side.