

In practice, yes. IF IMPLEMENTED PROPERLY it would be extremely unlikely for an attacker to get in.
For example with a proper implementation of TOTP it would require an attacker to guess the correct number between 0 and 999999 in less than half a minute. Most services make you wait a little bit (often less than humans notice) between attempts and don’t allow infinite attempts, so an attacker would have to be unimaginably lucky.
There are sadly lots of huge companies that DON’T IMPLEMENT 2FA PROPERLY. Sony Entertainment (account for PlayStation) for example. So a unique and long password is still important.
Lots of these apps let you export the entire vault as a file. I use this to import it on other devices. I currently have it on my phone (Aegis) and my pc (OTPClient) and is very satisfied with the experience.
I also have encrypted backups on a USB flash drive, an external HDD and five separate cloud services. I trust this solution.