Not really. Sure, that's a part of it, but it's way more than that.
For years Ted and Gute mostly ignored special teams in terms of drafting, signing, or keeping players specifically for that purpose. They cheaped out on special teams coaches a couple of times and that cost them as well.
Ted just filled the team with draft picks and UDFA's rather than bringing in veterans, even in the years where they had CAP room. He had some truly awful drafts at the end and did nothing in FA to compensate.
They haven't had a truly capable weapon at tight end in what, five or six years and Ted/Gute's way of addressing it was picking Deguara - ugh.
Murphy allowed Ted to hang around a couple of years too long and both he and Ted allowed MM to coach one or two years too long. Murphy also forced ML to keep Pettine (cheaping out) instead of letting him bring in his own DC.
That's just the ones I can quickly think of, I'm sure others can think of more.