If the phone is fresh and free from all kinds of malware, then keeping crypto on the phone is not that risky. You should not keep too many funds on an online device. You should only keep the emergency funds that you might need when you are out somewhere and need money, so you can sell those funds and get instant cash to complete your task.
The recent discussion that came up is about losing your sim, that's the most important one which we have already said that locking the sim will also help in order for anyone not to ask for a password request on your banking apps or centralized exchanges.
SIM card theft is actually a critical issue and most of the time people ignore it. Through this Sim a thief can bypass 2FA if they want through which they can access your mobile banking or other important services
Although to access current banking services and send funds, both a password and 2FA are required since they can bypass 2FA but won't get the password they may need to provide other documents or information to reset the password which they don't have. In that case the thief won't be able to do much but not all banks that secure
