Possible, but gamblers ruin seems unlikely while so much of the market is still played actively.
Easier to understand, and closer to reality IMO, is a simplified market with one dude who gets slightly positive average market returns with ten trillion dollars and 999 dudes who each suffer 50% losses on one invested dollar each. There are 1000 total investors and 99.9% of them underperformed so the "average" individual return is approximately -50%, no matter what the market does as a whole.
All of those little fish just don't matter, when there's a whale in the pond.
Of course the reality is slightly more complicated, because invested assets don't set prices, only transactions do that. The whale would have to be buying and selling to himself (or another whale), and putting new money in to raise the prices, but that's literally exactly what happens with pension funds that deduct from every employee's paycheck, or insurance companies that invest their float. Institutional investors are driving this train, not you and me.
The whole thing is a shell game anyway. The Fed can make up money at will, and with moderate tinkering we can put it into stock prices, or wages, or infrastructure, or long term debt, or dead foreigners. Remember that stock prices are just the last price one person paid for a share, not what the share is actually worth and certainly not what every single share is worth. Shares themselves are just as made up as the dollars we use to buy them.
The whole system is just a score keeping system designed to incentivize economic turnover, so that people will work and buy and consume and work some more. The Fed makes up dollars and then a company makes up shares to trade for those made up dollars, and along the way some individual humans amass power and control over other individual humans. And if we're lucky we also grow some food and build some highways or hospitals so that people can live out their short little lives with minimal suffering.
That's all the economy is. There is no objective store of value, there has only ever been human labor that generates work, and the select few (royalty, etc) who profit from that labor by telling everyone what to labor towards. Companies aren't themselves worth anything, they only have worth because of the products and profits they promise to produce in the future, at the direction of their leadership, and through the efforts of their employees.
"Labor is the source of all value." Go ahead, look it up and read all about it. Everything else is part of the shell game.