The name quarantine itself comes from a preventative isolation practice.
But lockdowns during pandemics have been practiced occasionally, but always at the city level, due to the nature of governance during past pandemics. Famously Newton and Shakespeare did work during London lockdowns, and some Italian city states distributed fixed rations to peasants to help them stay at home.
What’s new isn’t preventative quarantines, what’s new is global travel and communication.
And I think your second statement is false, preventive isolation en masse was practiced (to the extent possible) during bubonic plague.