Not sure exactly what you’re implying about how we look at people 100 years ago— If you’re referring to how “primitive” that age now appears to us… think about it this way:
The difference between the year 1300 and 1700 in terms of technological and cultural development was in many ways not even as great as the difference between, say, 1880 and today. Change is accelerating, and the next century is poised to see change at break-neck speed.
Only in the past 30 years was the internet developed. We’re now seeing the beginnings of automation, supercomputers that are on our person at all times, video conferencing, social media, augmented and virtual reality, robotics, self-driving/electric cars, commercial space flight, drones, usable jet packs and flying personal vehicles, nanotechnology, CRISPR, 3D printing, etc. etc… all these things and more are just in their infancy, and culture changes along with them. These technologies themselves will drive faster advancement. Most of these things could just barely even be imagined by people 100 years ago.
The next 100 years will (once again) see technological and social change unlike anything witnessed in human history. In other words, people looking back at us 100 years from now will see a society appearing even more distant than we see those 100 years ago.