We understand the usage and meaning of the term middle class VERY differently

The classic definition of middle class was, as far as I learned it, making enough money that you could afford to pay for your family's expenses without needing your wife to also work.

This came out of the poor working conditions in factories in the 1800s, where people often were hurt, maimed, or even killed (compared to today, this was quite common). If you made enough money that only one family member had to suffer (at this time it was always the husband), that was the bare minimum to be considered middle class. This was regardless of income, it was more about what you could afford.

Prior to this, I'm not sure middle class was really much of a concept. Most groups were separated by trade and upbringing, and pretty much overall separating the low class from artisans, merchants, nobility, and royalty, with no real middle class afaik. It was, for example, quite common for artisan families to all work together

Edit: i feel compelled to share that i studied history for my degree, and i am sharing one of the definitions i was taught.