>> It's only hard to tell if you don't talk to the developers who were working in the late 90s.

I think you mean "working ON it". Talking to developers as a broad group from that time wouldn't necessarily produce any useful information.

The person you replied to was himself a developer working in the late 90s. During the late 90s, I talked to a lot of developers, but only a small percentage of them were on Y2K jobs.