Those funds are not paying real dividends, rather, they are selling off the investor's principal and giving it back to them and calling it a dividend. It creates the illusion of monthly income, but in reality, it's not. Think about it... no stock pays out a 10% dividend in real life, much less 20%.
As long as the market is going up (and we are in a crazy bull market), they can keep "affording" to make high payouts without tanking their NAV price ("dividends" get subtracted from the NAV). But long term, you're just handicapping your own ability to gain from future market rises, because any rise that occurs is paid out to you immediately, instead of being reinvested for the long term.
Look at the graph below (which I assume is the fund you're referring to), the darker orange line indicates performance if dividends were "reinvested". This is real performance minus 20% (dividends would be taxed at 20% before being put back in). The lighter orange line is the actual NAV, post disbursements, which has remained pretty steady despite the bull market.
In other words, if they paid out 2.5% as a dividend this month, it's because the market went up by that much, or more. But had you kept the money in, and not had to pay 20% on the dividends, you would be in an even better position for future growth. So if you're still in the accumulation phase of life, steer clear.
And I won't even get into their ridiculously high 1.7% fees...