AI won't disappear definitely. However, more graduates will enter market as we move forward. Thus there will be more supply than demand which leads to drop in salaries.
This has happened in many markets in recent years. Don't you recall big data hype around 2007? You would be considered as God if you can barely install Hadoop back then.
Competent big data folks still pull down $300-400k fairly easily. I’m talking about people who _really_ understand the field and have a track record, not “graduates with a degree”.