It's similar in percentage terms, perhaps even a bit more concentrated. Lowell, Massachusetts had a population of 20K in 1840, with maybe 6000 working in the factories. Total U.S. population was 17M at the time. Compare with Google alone having 60K employees spread out across dozens of offices.
Lowell was the only such center of manufacturing in the country at the time, much like how Silicon Valley is considered synonymous with the tech industry. There are other tech hubs, though, and other companies, and tech is already starting to bifurcate into sub-industries. I'd actually equivalent 1840s Lowell to the Massachusetts Miracle of the 1970s, when the MA economy was rescued by the arrival of info-tech firms like DEC, Stratus, Wang, etc. (ironically, DEC was started in a former textile mill, and Wang Labs had its headquarters in Lowell). The current point in history seems more like the 1880s or 1890s, when the center of industry had moved to the Great Lakes region and the basic technologies had bifurcated into the steel/oil/shipbuilding/railroad industries.
We think of factory work as employing the whole population because the oldest folks alive today only have memories of the 1920s and onwards. What are these big industries that lifted people up the chain? Automotive, aerospace, airlines, oil, manufacturing, plastics, chemicals, retail, consumer goods, media. In 1880 the car hadn't been invented. The plane hadn't been invented. Plastic hadn't been invented. Radio hadn't been invented. TV hadn't been invented. The department store hadn't been invented. Consumer goods required all of these.
Similarly, I suspect that the great industries of the information age have yet to be invented. Or they're in vary nascent, experimental forms today, like drones and cryptocurrencies and hyperloops and robots and self-driving cars (which'll probably end up being pods, eventually).