We did feel pain. You could mitigate the pain by never making mistakes (like by ensuring all your cron scripts log to somewhere in /var/log, or that you have alerting, or that you always put them in crontab).
But also what we consider to be painful has evolved. When all systems were to some extent a hand-gardened entity, maintained by some specific system administrator, it was easier for them to have a personal standard. It didn't matter if I used cron.d and you used crontab, as long as on our own systems we kept one method. Increasingly, servers are more ephemeral, more horizontally scaled, and more automated, and systemd timers are just easier to work with in that model.
In a decade or so, I'm sure we'll have further modified how we handle systems, and something else will come along that solves painful things about systemd.
But also what we consider to be painful has evolved. When all systems were to some extent a hand-gardened entity, maintained by some specific system administrator, it was easier for them to have a personal standard. It didn't matter if I used cron.d and you used crontab, as long as on our own systems we kept one method. Increasingly, servers are more ephemeral, more horizontally scaled, and more automated, and systemd timers are just easier to work with in that model.
In a decade or so, I'm sure we'll have further modified how we handle systems, and something else will come along that solves painful things about systemd.