Totally agree with your take. It's easier to criticize after the fact. Nevertheles, your point is valid and spot on. The Bills have failed to adequately solidify the offensive line. A critical error which has been a major reason why the Bills can't get over the hump. It's football 101 to have a strong Oline. Look at the Chiefs for a prime example. Reid built up that line very quickly. Mahomes lost Hill and has average Joe WRs. He's still elite and productive because of his Oline. They advance to the Championship game with a much worse defense than the Bills. The primary difference is their Oline and pass rush.
The Bills have whiffed on Ford and Stafford was a poor pick up. Not to mention the neglect of drafting available Olinemen. Brown is an unknown and a work in progress. Mostly he's a liability and not reliable.
The draft picks on the Dline have been flat out bad. Big misses on premium draft picks. Eventually, a team's failure to draft adequately and strengthen its weaknesses leads to negative consequences. Those are magnified in the playoffs vs elite teams. Make no mistake about it that's exactly what we saw on Sunday vs the Bengals.
Fast forward to now and the Bills are handcuffed by the cap. Beane is fantastic at getting creative and manipulating the cap. However, he can only do so much. He pretty much admitted it in his presser. Beane gave fans a lot of excuses which some had validity. He pounded the table on how the current players will improve their play. I'm not convinced they will. I'm convinced the Bills will suffer injuries next year. That's just the nature of the business. Will the excuses begin again?
Imho, the Beane, McD, Fraizer, and Dorsey combination is losing its steam. Losing its mojo sort of speak. Very clear with its playoff failures. Seems like they can build a winning culture and excell in the regular season. However, they have failed for 6 years straight to get over the hump. The last 2 years has absolutely been disappointing. This team hasn't even competed in a AFC championship game. I don't see a likely path where this changes. Running it back with the status quo seems like a losing recipe.