This reasoning was always flawed. The Stock Market is not real life. It consists of the opinions of a bunch of guys who sit in towers in New York, London, Shanghai, etc... In theory there are fundamentals that should drive the price, but in practice the market is not rational. It's not a good metric for the long term health of a company. Even worse, Goodhart's law applies in spades:

"When a measure becomes a target, it ceases to be a good measure."

Time and time again we see CEOs playing games with the stock price in order to get a big payday. We see management sacrificing long term stability in order to maximize their year end bonus.

Imagine if every time you remember a now dead company do a stock buyback they instead invested that money into R&D, or simply lowered their prices to be more competitive in the market? Maybe they paid their employees better and didn't have constant turnover problems and had higher quality output. How many of those now failed companies would still be around today?