I would wager that taking a shower and brushing your teeth are not something you think about. They are autonomous and there is no chance that you would forget to do them. If you listed the things you do each day that are recurring tasks but aren’t autonomous, you would be surprised how many things you have to remember. Unlike taking a shower, the same can’t be said for taking out the trash.
If I can make a blanket recommendation, you should be using two-factor authentication for any website or online service that provides it. No matter what that second factor is, be it SMS, one-time passcode, or security key, it decreases the likelihood of your credentials being compromised. Unfortunately, the majority of services only provide two-factor authentication (2FA) using the SMS method by texting you the temporary code. By having your phone number be one of the critical pieces to get access to parts of your digital life, changing your phone number becomes a terrifying prospect.