Unfortunately in the modern game it is. In the old days finishing 8th but winning the FA Cup was deemed more of a successful season than finishing 2nd in the league but not winning the FA Cup. That has long changed. I don't like it, and morally I don't agree with it but the undeniable fact is finishing 4th IS more important (and therefore a better achievement) than winning the Europa League, FA Cup or League Cup.
Unless you finish 6th and win the CL.
If we had got in the CL this season then that would have opened doors to more success for us, though obviously those doors are now closed, so if the CL is not success, then it is certainly a gateway to success