This premise doesn't jibe with products that are "always on". Support 5hrs/day? I hope "great support" isn't part of your value prop. Devs can't even be reached because they log out of slack, etc at 1pm and over the weekend? I hope "uptime" (riiight) isn't part of your value prop. As a consultant we do lots of new product development for clients where uptime and support are a big deal, especially during rollouts/launches where we're encountering a flood of new issues (UX and technical), going totally dark after 1pm weekdays isn't a remote possibility.

Having said that, we very rarely actually work more than 35hr/week or on weekends. But we do put my personal phone number in our SOW for CRITICAL issues (haven't been called yet). So yeah maintaining a sane work culture is critical but telling everyone to completely unplug at 1pm is nuts IMO.

This article isn't outlining every details obviously and maybe the example company really doesn't care about uptime or quick support (desktop app for enterprise??). And maybe they are glossing over the fact that every week there actually is someone on call but most people unplug at 1pm. If so, that sounds pretty reasonable!