I agree to an extent, but it's important to realise such rules aren't "free." There's a cost to holding someone's seat. Employers whole heartedly replace them

I agree to an extent, but it's important to realise such rules aren't "free." There's a cost to holding someone's seat. Employers whole heartedly replace them, because they're entitled to come back. So, they need a small 6 month replacement that may or may not become a permanent need. For most jobs at large companies, I totally agree. They should be able to handle it. But, marginal cases will still exist. Niche roles, senior employees or smaller companies. Image a 200 person startup where a team lead or similar takes her 6 months. The team is now in limbo. I like the idea, just saying it comes with downsides too.