By what metric is the market more biased towards professional traders? By the metrics of cost to trade, spread, barriers to entry, expense ratio etc. it’s never

By what metric is the market more biased towards professional traders? By the metrics of cost to trade, spread, barriers to entry, expense ratio etc. it’s never been better to be a small scale investor. You have more opportunity to trade now, in more markets, with more information & instrument options, for cheaper than ever.