It seems so strange to me that everyone buys the bullshit that personal data is worth very little.
The data brokerage industry is a multi-trillion dollar industry. Yet, there are only ~8 billion people in the world, many of whom don't have internet access or have very little data being traded. Thus it's reasonably safe to assume that an average regular internet user's data is worth somewhere in the region of $1,000 per year.
These companies don't do anything with the data. We create the data, they collect it and sell it, then whoever buys it is the one that actually makes something from it. If we allow the brokers a very generous profit margin, they are still stealing $500-700 from every one of us, every year.