In 1997, monitors and TVs were much more different technologically than they are today. Today TVs and monitors are much closer in underlying technology/capability (discrete pixels, same video signal standards, similar illumination and color tech). LCD monitors were available in the 90s (13" was fine for a monitor, not for a TV) and were understandably many times more expensive than the hitherto strictly CRT TV tech.
Even between CRT TVs and CRT monitors, they weren't even signal compatible with each other. Maybe with a discrete graphics card that could convert pixels to NTSC/PAL outputs? Was that ever a thing in the 90s? Modems to convert cable signals to VGA output? TVs had scanlines because the signal they received represented horizontal lines as modulated analog signals (+ an analog audio signal) which were displayed back as lines after demod, rather than mpeg-bits received via modulated digital signals which were displayed as pixels. All of this meant that other than sharing the presence of a cathode ray tube, monitors and TVs were quite technically distinct. So yeah, in 1997 there were very good reasons why monitors were more expensive, which have since disappeared as the media world converged on digital transmission + output. TVs and monitors are more colinear in the fundamental tech and protocols today, end-to-end, with the differences mostly being auxiliary or in specs.
IIRC where I grew up, the price differences were even more ridiculous in the 90s but because market conditions amplified the technical differences — a TV was a mainstream household appliance, and anything PC-related was enthusiast/technologist hardware.
There are several no-name monitor manufacturers from China too, and their ultra-cheap monitors are similar in price to the ultra cheap non-ad-revenue-TVs (with similar low quality tech specs usually), or price differences more obviously explained by feature differences.