Yeah, that won't work well with a bunch of legacy stuff and a TON of companies are going to fuck up not renewing or building an automated renewal process for various critical but obscure targets (this already happens all of the fucking time, even for huge companies).
So how does it not work with legacy? What legacy shit actually uses certs? Nothing in my mfg/prod/semi world used certs.
And even if it did, how does renewing the cert not work?
Place I work at uses a PBX that only allows you to install a cert manually via GUI. We tried to automate it but literally cannot be done any other way. Shit is stupid but we can't move to something else because the renewal is so cheap and management doesn't want to deal with setting up something new.
So why does it need a cert? For a fucking pbx? But I see your point if it does and is manual, you fucked.
So how does it load said cert?