The question is who is "they?"
I'd argue it's not so much the contractors, as it is the Air Force. In particular, AFMC and ACC. Contractors gonna contract, they're gonna occasionally be slow and provide substandard product. That's not ideal, but that's just reality of the supply base for military aviation.
A former professor had a different way of putting it - the difference in standards between military and civilian aviation is why, when a 737 makes a smoking hole in the ground, the heirs of each person sitting in the back gets tens of millions. When a F-16 does the same, the heirs get a couple hundred grand in SGLI money and a folded flag. A morbid aspect of the difference in civilian and military aviation.
And the topic of "counterfeit parts" is obviously incredibly concerning, but so far it just seems like a red herring in this case. It makes for good press, but hasn't yet been attributed as causal to the incident.
In theory, AFMC and ACC should be the "adults in the room," advocating for keeping the best possible hardware in the hands of the warfighter. In the case of AFMC, it would be the System Program Office (SPO) for the F-16 and whatever SPO handles the ACES-II seat and components.
One would hope that, due to the criticality of their application, all mods, TCTOs, etc related to the ejection system would be given the highest priority within the Air Force enterprise. Everything about this accident seems to point towards the ejection seat mods being treated the same as any other mod on the aircraft, and scheduled when they'd be the most convenient and least manpower-intensive.
Either way, lots of missed opportunities:
TCTO 11P2-3-502 was issued for the shorting plug installation. When the plug wasn't available in 2017, ACC decided to push the install 36 months, to the next seat maintenance opportunity. Why was such a safety-critical mod allowed to be pushed three years to the right? Who made that call, and what was their reasoning? What was the original compliance deadline on the TCTO?
The shorting plug was out of stock, for some reason. Did someone from one of the SPOs go beat down the door of the supplier to expedite orders for the shorting plug? Did someone search out an alternate source? Or did no one take any action, and accept whatever slip they manufacturer gave them?
The DRS reached it's life limit, and it sounded like ACC asked for three individual six month extensions. ACC is looking to the "big brains" in the SPOs in AFMC to provide well-reasoned technical guidance on whether or not the life should be extended. Did AFMC do any kind of no-shit analysis and come to a well-supported conclusion? Or did some desk jockey just sign it off to keep the boss happy? In hindsight, the combination of a required TCTO, along with expired service life should have given someone pause.
When the shorting plug became available, ACC didn't install it on the aircraft. When the replacement for the DRS became available (the MASS), ACC didn't install it on the aircraft, either. Instead, they pushed all mods to the next available maintenance opportunity. That's great for efficiency in manpower and aircraft availability, but poor for safety. Again, an OK path if your mod is some mundane change, but poor if your mod is safety critical. Goes back to what was the deadline on the shorting plug TCTO? Who set the deadline, if it was pushed, who approved the push, etc.
The question of manpower resources at Shaw comes up, too. I'm long since removed from any kind of military flightline environment. But the stuff you read on social media (here and elsewhere) seems to indicate the scepter of volunteering, bake sales, SARC CBTs, and everything else but your primary duty continues to be the focus. If some of that nonsense was diminished, would maintenance at Shaw have had the bandwidth to do the seat work sooner, and not wait for the next "convenient opportunity?"