Yes. I totally agree with what you just said mentioned above, because in as much as it's not advisable to store all your crypto assets in one wallet, another important factor will be the need to properly keeping that your 12 key phrase in a safer place, as that's the only key to accessing your funds. Whereas, USDT or BUSDT can be an recommended alternative after Bitcoin
Firstly it's BUSD and not BUSDT, secondly both stablecoin (just like majority of the stablecoin available in the market) are centralized and not to be trusted for long term holding. These stablecoin just like UST can collapse at any moment or get depegged (trade below the $1 price that it was meant to be stable at). Sometimes they recover while other times they mightn't. The most recommended way to hold your profits is in Bitcoin. With Bitcoin you are assured of your funds not going to disappear as we see with the altcoins. If you aren't comfortable holding it in the space then you can go traditional with fiats.
Don't over trust any stablecoin in the industry as without the support of the community, all of them can collapse like we have seen with previous stable-like projects. As for the tips of becoming a successful holder, my advise to anyone embarking on this is to put more focused on where you store your coins as security of your assets should be your number one priority as an investor.
It is still doubtful to keep stablecoins even though it feels safe because it is the same as traditional fiat, but we have to look at other facts about other stablecoins that many have collapsed and cannot be reached at normal prices anymore so I always avoid this to store stablecoins with long time ago, obviously I didn't venture except bitcoin being the only hope.
Successful holders keep their assets for long term increase not with stablecoin, but bitcoin of their choice, and also don't choose altcoin for hope in the future because it won't make us successful but bitcoin can come back with ATH price because it has 4 cycles years that will be history repeating itself.
Most importantly never store assets on an exchange, choose an asset repository with either our managed security or having 12/24 word seed phrases.