Not sure it's really worth drilling down on this, but what in your view (and in Fangraphs) is an "above-average" starting pitcher? I suspect it's someone like Vince Velasquez, someone who gives you 1-1.5 WAR on average. 30 WAR in 7 seasons sounds like a #2 starter to me.
I'm sure it's also true, even though teams are going to figure out a way to carry however many guys they want, that combining last year's 15-pitcher class with whatever the 2021 draft produces does make lower level guys more disposable. It's possible that after Instructional the Phillies already realized that Ragsdale wouldn't crack the Clearwater rotation (the Threshers now being low A) and was of less value to them as a reliever or extended ST guy.
We are traumatized by the last two bullpens, but it's still worth signing proven players and it's also still worth acquiring as many guys like this as you can. Last year was a perfect terrible storm in that there was no time to really let any kids/fungibles rise to the top - or to have patience with the ups and downs of struggling vets.