What exactly does anyone feel has been lost here? Perhaps Italians have mixed feelings of wounded national pride and thankfulness that the Colnago family received substantial financial recognition for their decades of dedication to advancing cycles and cycling - but this is mere speculation.
Having only ever owned one (or I'm not certain - possibly two) Italian bicycles (the budget Maserati city bike was donated to a charity auction at a Cirque, and fake Colnagos are a "thing" and I may have had one that my son never took a shine to - so I sold it on), and as a cycling Anglophile, I may have an emotion-free perspective. I have far too many Raleighs (my wife's words, not mine).
Their offerings in their heyday (sorry for all the parentheticals, but that's how I write... post ww-II to circa 1980) have quite an appeal to me. The marque was not without it's own bits of drama, having in varying degrees of benevolence (or opportunism) acquired and absorbed many other beloved marques... Rudge, Hercules, Robin Hood, Dunelt, Sun, Carlton, etc. Haunting other communities, it is clear that there is nostalgia and followings for each of those which were bought out. This said, there's also quite a lot of nostalgia for Raleigh also. I happen to have a rather "weak spot" for their lightweights from post WW-II to about 1980.
Sorry for the bit of digression. I do get nostalgia. It can take many forms. What I hope I've been illustrating is that, while this sale is actual news, I don't see it as an event to mourn. Celebrate the great bicycles that Ernesto and the family built. If you like the direction the new owners take, great. Support them. If not, they probably weren't meeting your hopes these last couple years/decades. Raise a glass to them if you like, but don't mourn. As long as the Earth takes laps around the sun, there's going to be change. If there were no change, would we even have gotten to hobby horses? Would the TdF have been raced on ordinaries? Would we even have any better appreciation for lightweight steel bicycles and have the nostalgia that many of us do for them.
I say, "well done" to the Colnago family, and wish them the best.