As someone stuck managing bare metal servers behind closed networks, can I use these tools to get insights and alerts on how my servers (and docker services) are doing?

It all seems cloud native these days and I'm not sure if it's worth the time investment to learn these tools.. Our in-house solution is a set of systemd services to collect data (write to log files, read lines from log files) and push to a remote nodejs/express service that holds recent values and averages in memory to display a spreadsheet-like dashboard with colored cells (signaling status) and basic sms/email alerts..

It works, it's fast, it's cheap, but there's many things missing (APM specifically, log analysis etc)