Answer is simple.

While systemd can restart crashed processes, Process Watchdog goes beyond basic service management, making it ideal for trading, alert, and analysis bots:

• Heartbeat Monitoring – Unlike systemd, which only checks if a process is running, Process Watchdog ensures the bot is actually functioning by requiring it to send periodic heartbeats. If the process hangs but doesn’t crash, systemd won’t detect it—Process Watchdog will.
• Process-Aware Restarting – Some trading bots or scripts don’t fail completely but instead freeze or become unresponsive. Process Watchdog can restart them even when systemd wouldn’t.
• Lightweight & Easy to Use – Process Watchdog doesn’t require systemd configuration files or deep Linux knowledge. It works via simple file-based control, making it easier to integrate into custom setups.
• Statistics Logging – It logs process starts, crashes, and heartbeats, allowing you to track stability over time—useful for debugging and optimizing bot performance.
• Manual Control Options – You can send simple file-based commands to start, stop, restart, or even reboot the system as needed, adding flexibility beyond systemd.

systemd is good for auto-restarting, but Process Watchdog ensures your bots stay functional, not just running.
As it is a custom design system, it can answer any need, but systemd cannot.

I skip your second question as it does not matter who is who.