The biggest difference between the last two centuries and the rest of the past centuries, in my opinion, is nothing but material abundance. The Ancien Régime was replaced because with the advance of the Industrial Revolution the bourgeois or commercial class accumulated power to the point where the old aristocracy only represented a problem, then under the slogan of freedom and equality could get the support of great part of the people. The monarchies fell, however, the United Kingdom and the United States were already seeing the material result of the productive force after the invention of the Steam Engine.
The massive production of products brings about the reduction of costs, making accessible any infinity of products that in the past were totally unattainable for the common people, all this combined with the relative freedom not only economic but also social that was experienced in these Countries, such as freedom of worship, allowed the free practice of science, which, in turn, applied to industry in general managed to maximize industrial performance and produce a wide variety of products with different characteristics.
It is more likely that people can become more innovative and creative if they have more different materials, because humans have the ability to collect information, make associations, and apply solutions to different problems. In this way the citizens who lived after the Industrial Revolution had greater accessibility to products and materials due to the low costs generated by large-scale production and division of labor.
It is not a coincidence that in countries with closed, bureaucratic and planned economies there is no innovation, because for this to exist, the inhabitants have to enjoy abundance enough to satisfy their basic needs and then subsequently acquire products and different knowledge, which is generally applied to the industry and ends up solving a specific problem, thus increasing social wealth, but all this will not be possible if there is no greater supply than demand, because only when supply is greater than demand are prices low, and therefore products are accessible.
In short, market freedom is what allows mass production, giving greater accessibility to people, but economic freedom was not the only factor of innovation and growth, since freedom of worship was what allowed people will practice science openly.
So, could we say that freedom is what differentiates the most developed from the least developed countries?
Well ...... So what happens to China or Singapore?
In fact, while it is true that freedom ends up being quite profitable from where you look, and that regardless of whether profitable or not, must be defended by principle, the truth is that what probably marks the difference between the most and least developed countries, and between the last two centuries and the rest, it is the ability to mass produce, but not only that, but to increase the supply enough above the demand to make the goods and services accessible to the greatest number of people.