In regards to salary, sure that has increased. However my discretionary fund/bike fund has remained fairly consistent. When I was younger I lived at home or was in the dorm at college. Didn't really have any major expenses. Rent was covered. Meals were covered. Now as an adult have mortgage, car paymens, health insurance, life insurance, children's college fund, retirement, investments...etc. So my bike fund is basically the same. Any other questions?

That's why I never tell the whole truth, just something along the lines of "I got the frame for this-and-that-cheap on ebay¹ and put on a few parts."

¹which is usually fairly accurate

Yeah, for most of us that was in the past.
But for most people in the world that's still a reality.

And even for many people in 'modern' or '1st world' countries with a higher-than-avg GDP, the costs are incredulous.
Too often I'm asked by a friend to help them find a good, entry road bike so they can start riding along with me (or ride with their family) (or ride to work) (and so on) - but the budget they're looking at always hovers between $500-$800 TOTAL (helmet and tools included). I don't mention to them that there are wheels which cost $5kUSD per pair, nor brakes that per pair cost more than their total budget - but if it eventually comes through in conversation, its usually met with complete shock.