I think it's a matter of supply and demand. Five years ago, your colleague's skills may have been highly sought after, with low supply and high demand, leading to higher salaries. But now, the supply of people with those skills is higher, while demand may be lower or stagnant. This gives companies more options, so they can lower salaries and easily replace employees who don't agree.

To stay competitive, we need to constantly improve our skills and perhaps take on more responsibilities to become indispensable to our employers. Additionally, diversifying our income sources can help. The resources are limited, but the number of people entering the job market keeps growing each year. This increases competition and can lead to some people experiencing economic hardship.