The calendar is a funny thing. Despite originally have something to do with moon cycles or whatever, it’s now basically just a thing we accept as eternal. July is a month that is in the summer if you live in the northern hemisphere, and it makes sense that is has 31 days while some months have 30 because that’s what the calendar says. Essentially, it’s a self-serving model that consists because it’s basically fine.
The French Revolutionaries had other thoughts. Starting July 15 1789, they started a French Republican Calendar. Each month had exactly 30 days, except for a few extra that were made as holidays, and a Spring year day every four years known as the “Day of Revolution”. There were 3 months per season, and most importantly in my opinion, every day of the calendar year had a unique name. For example, my date of birth (07/18/2000) is 1 Thermidor CCVIII, also known as Corn. Here’s a converter if you’re interested. Additionally, happy Lentil Day!
The adoption of this system was a beautifully bureaucratic mess, if you want to read about it here. To summarize it, even though this new calendar is just more reasonable and easy to understand, it was difficult to implement into society, and amidst the earliest years of your revolution is probably not the best time to be messing with the very concept of the year. I think parallels can be found between this and the refusal of America to adopt the metric system entirely. (No, I don’t care that you dislike base 10 numerals, it’s not that hard. 5/2= 2.5, get over it.) Ultimately, the customary system works, and unless we find compelling reason to change, it’s probably not worth the effort.