As of late, crypto has become extremely popular due to the negative effects of COVID-19 in the mainstream economy. People are starting to consider crypto to be a safe-haven against the traditional monetary system empowered by banks worldwide. Yet, the vast majority still relies on Fiat for day-to-day transactions because of its price stability and widespread acceptance in the mainstream world.
Look outside and see how people live and what they are doing, you'll clearly see that they don't need crypto for day-to-day activities and fiat is enough for that. Do you want a volatile coin that can bring you chicken today but maybe you won't be able to buy egg tomorrow? Or the opposite can happen, you can buy egg today or be left hungry but you may have chicken tomorrow. Yeah, price is very volatile and that's why people prefer fiat. They can use USDT or any other stablecoins but fiat just does the thing!
With the advent of privacy coins, people can enjoy true financial freedom like never before.
First of all, Financial freedom starts from the moment when you are able to feed yourself without the help of others. In poor countries, that's impossible. When you are financially free, then bitcoin and cryptocurrencies just can fulfill that freedom the way you mentioned.
Privacy coins can become attractive tools for illicit activities because of their untraceable blockchain ledger. Despite all of the benefits privacy coins provide, criminals still rely on Fiat for all of their nefarious actions.
Where are you from? There are old generation criminals, from 70s, 80s that don't have any idea what the hell bitcoin is. Bitcoin isn't anonymous btw and the less criminal uses it, the better for everyone. And finally, those coins are converted into fiat, we never measure the price of things in fixed btc prices, it's always volatile as price in USD changes.