Steemd could be running, but not ready to accept connections / witness blocks. So you'd get false positives about it being "active" if you were just checking for a running process. The node takes a good 10 minutes to spin up and during that time, it's going to appear to be running.

On the other hand, with the open port... If you wanted to check connections to steemd, you also would have to enable one of the RPC endpoints or plugins for that to work. You probably don't want to use any of those settings for a witness node. I'd also rather not open any ports on the firewall or connect to it at all.

IMHO this is a better solution than those options. I had a node completely melt down and I missed 2 blocks in 2 minutes, then it failed over to the running node.

To each his own though!