This is the risk exposure we are talking about it here but many take it lightly and then regret later on.Some have also not enabled 2FA security features while those have enabled it they use the same device where they have authenticator download to get the code and login on the same device so what if it's compromised? I also recommend different devices for security but you should know how to handle them as well.
I meant it. It does not make any better thing for security if we have all in one device. If a hacker can hack our email, our account login information on that device, it is possible to hack 2FA on that device too. So 2FA is a protection against hack, it must be installed on a different device that we don't store a layer 1 information of our accounts.
Having two different devices are good enough for me. One for email and login my account and my phone is only for 2FA. They can not get anything if only successfully exploit one of my two devices.
Regular people need to diversify their life not only on the number of devices they use but also on the number of online accounts they have.
An easy way to do this is with their email, I know people that use the very same email for everything, which means that if at some point a hacker gets into that email then they can get all kind of information from them, but if instead they decide to use a different email for their personal matters, the different exchanges they use and the casinos in which they like to play then even if one of those emails got compromised they will lose only a limited amount of information.