Not sure old steel rides significantly worse than new alloy .... does weigh more, though. Point is, when you have a garage-sale frame and a bucket of mismatched parts, you can either toss the whole mess or n+1 for less than a bargain-basement new bike ... or about the price iof a decent rebuilt C&V. Hmmm ......
In my case I had been lugging that damned frame from home to home for so many decades, I wasn't about to let ti go without it lugging me around for some miles.