We want to inhibit when running stuff like pacman, wget, cp or mv

There is already a separate systemd-inhibit command that does exactly what you need. Trust your users, they are capable of googling it (most of the time).

Only pacman and wget will benefit from suspend inhibition, because it will prevent breaking network connections. cp and mv will resume working just fine even when you hibernated your laptop while cp was executing. And in that case it's less bug-prone to scan your system for active TCP connections to external addresses instead of adding a hack wakelock inside your terminal or inside wget.

It is also a poor idea to mess up with system-wide settings from some command when the user does not expect it, you'll likely to get a thousand invalid bug reports that sleep mode is broken when some service randomly decides to use wget to continuously read from local Unix socket.