If you’re simply listing asset classes such as stocks and bonds, I see no issue with also mentioning digital assets (I wouldn’t mention bitcoin specifically) – just as I’d see no issue with mentioning other asset classes, such as real estate or gold. I’d have my compliance department approve any ad before using it, to make sure the proper disclosures are present; you want to be clear if you’re offering an asset or a security investing in that asset (a REIT vs real estate, or gold ETF vs gold, or GBTC vs bitcoin). And be sure you’re not violating your firm’s “selling away” rules.