New investor here 26y/o just started few weeks ago, in my fidelity acc both in my roth and taxable account I have fskax/ftihx going for longterm, my question is that people around me have been saying to trade my MF’s to an ETF especially in my taxable cause they said its more tax efficient and mutual funds are outdated, is there some truth to this? Dhould i transfer my investments or just let it be cause it dont really matter?