Josh Brown: Here's the reason Wall Street hates the bull market in stocks so much

• Josh Brown says active managers on Wall Street may be concerned about their jobs.
• The more the bull market is led by indexing, "the less likely it will be that there'll be big bonuses, there'll be an expansion of business for these people," he says.

Enthusiasm about the stock market's rally is "absent" because active managers on Wall Street are worried they may not have a job soon, money manager and popular blogger Josh Brown told CNBC on Friday.

The more the bull market is led by indexing, "the less likely it will be that there'll be big bonuses, there'll be an expansion of business for these people," the CEO of Ritholtz Wealth Management said on "Halftime Report." "And I think if you can't get pros excited, it's tough to get euphoria amongst the amateurs."

The author of the widely read blog The Reformed Broker added that perhaps the negative sentiment has prolonged the bull cycle.

In the past decade, there's been a shift from active to passive management strategies, such as index funds, which replicate a stock index like the S&P 500, and ETFs that track the market.

Billionaire investor Warren Buffett has even said index funds make the best retirement sense "practically all the time."

Since the presidential election, the Dow Jones industrial average has risen more than 16 percent, the S&P 500 has gained more than 13 percent, and the Nasdaq composite has surged 20 percent as of Thursday's close.

Some analysts attributed the stock market's rally to proposed policies from the Trump administration, including looser regulations, infrastructure spending and tax reform.