The SSD I have in my system now is from 2011. No issues.
It's true they will wear down eventually, but not within the time frame your system can be expected to remain functional and relevant. It's highly unlikely for normal operations.
Defrag is not required for an SSD.
Mechanical hard-drives have other limitations. Namely moving components. They will degrade over time and eventually stop functioning. An SSD will outlive any mechanical hard-drive, almost guaranteed.