You know what I've learned after all these years. I may not know "what works", but I sure do know what won't.
Gosh, you just said one of the things I dislike the most about the old timers. They tried something, they failed at it, and the conclusion they bring to the table is unpossible!
To be sure, by all means yes, I want to hear about what went wrong the last time around, but one failed attempt does not prove much.
As I remind them every time, the real lesson they bring is that, if we were to do exactly what you did, back at that moment in time, we would fail... likely.
Instead I refocus the meeting on whether it really is different this time around: has technology evolved? the market place matured? are we architecting the solution differently? better team? etc. /rant
And you just made one of the rookie I'm-a-manager/architect-hear-me-roar ASSumptions that I detest as a rational individual: you put up your own strawmen any time you run across someone that sounds like that guy you disagreed with but weren't able to intelligently understand and work with to arrive at a common understanding and path forward.
We had a crotchety old bastard at my office a few years ago. People would dismiss him out of hand because he was gruff and unsympathetic to the care and feeding of the youths' fragile self-esteem; i.e. he would call a stupid idea a stupid idea. Turns out after a couple of failed efforts at a few things that he was exactly right on all counts. And the projects that he worked on that went well, went well because people trusted his knowledge enough to discuss his answers from a position of accept-then-attempt-to-disprove rather than your-presentation-sucks-we-aren't-listening-to-you-neener-neener.
So, yeah, I'll take a competent, gruff old asshole over an inexperienced and self-important noobie any day. Related: always strikes me as ironic how the Social Justice Warrior/Bleeding Heart type tends to be so dismissive of the Old Bastards in modern western societies, *in spite of the preponderance of evidence of their competency.* /smh