Trader Tax status is MTM. https://greentradertax.com/trader-tax-center/trader-tax-status/section-475-mtm-accounting/
As my understanding, you can have trader status and not be MTM. However, you can only elect MTM if you've qualified and chosen Trader Status.
I have an entity that has elected mark-to-market accounting IRC 475(f) for trading in securities. If you are doing high trading volume where the traded tickers repeat day after day then you pretty much have to do this election. Otherwise a life-altering surprise can await you at tax time due to "wash sales".
TTS and MTM are two different things. For an individual or entity to make an MTM accounting election, AND HAVE IT APPROVED BY THE IRS, the individual or entity must qualify as a "trader" or a dealer in the eyes of of the IRS. Enter TTS which has no "official" definition other than through case law study. Worth mentioning, is the fact MTM accounting is PERMANENT unless permission is granted by the IRS to change accounting method. TTS is a tax year-by-tax year qualification. Seek professional advise.
I see Investor is the number one answer so far. If you do qualify for Trader Status, what reason's are there for keeping Investor status?
You can qualify for trader status and MTM and still have investment accounts that are segregated from your trading activities.