Retirement age depends on so many factors, factors that can affect the quality of life after retirement. This can be, the amount of cash you have saved, the kind of business you have built to sustain you needs or investment made to cater for the future.
The best time or age to retire is unique to every individual, the Tech Boom made so many people retire in their early 40s and late 30s, many more did retire during the last crypto bull run and my guess is they're probably a lot younger.
Retirement age is the age when you have the required resources to cater for your needs and the needs of you family without asking for aid from others or the government.
Some may chose to continue working even after acquiring the resources, that is where choice comes in, and some may not attain such height even at age 65.
Which is the legal age of retirement in my country.