By NFL standards 30 is pretty old. Elite HoFers can extend but typically are role players over 30 vs stars. Obvs some exceptions but statistically most good players get 1 real contract after their rookie deal and most are out of the league come early 30s
Good thing the four oldest guys are all future hall of famers.
Derrick Henry just had a monster season at 31 and CMC is not a power back. He could be a slot WR.
We already discussed Kelce and Kittle comparison.
Brandon Graham had 11 sacks at age 34 two years ago but you are question is Bosa can play at 31.
Bobby Wagner just had a great year for the commies at 34 years old. Yet Warner will be too old at 33.
Sure maybe one of these guys drops off and is a shell of himself or they all decline and aren’t all pros anymore but this dumb narrative that the 49ers are finished because they are too old and expensive is ridiculous.
Your argument is essentially the team is screwed because 3-4 years from now a couple guys who are highly paid might not be all pros anymore. Meanwhile they will continue to draft and develop the next wave, augment in FA and the cap will continue to rise.
Eagles showed everyone the blueprint. Pay and lock up your stars and let everyone else walk and replace them with young, cheap, controllable players.
These guys will be core to the success / failure for the next few seasons but future draft and development will determine success 2+ years down the line as you said. Main point is nfl is a young man’s game and contributions beyond 30 are outliers. Won’t surprise me if a lot of these guys are cut, traded, or retire before the end of contract terms