Why is blockchain valuable?
Cryptocurrency is digital money. There are tons of different blockchains and even more different tokens. They all have their own price, but that's not the "value" I'm referring to. BTC trading at 23K does not represent the value and purpose of decentralized networks.
Blockchain networks are valuable to society for a few key reasons. The two I'm most interested in are...
We're constantly doing business in the real world without blockchain. Sometimes you buy goods and services from companies. Sometimes you strike a deal with another individual. There's invoices to pay, receipts to issue, escrow accounts to fund, lawyers to involve, auditors to ensure compliance, insurance to pay for, insurance to pay out, etc.
Each of these steps involves people who aren't really adding much value, but they're necessary to the overall deal. For most cases, blockchain probably won't 100% replace human intervention, but for the 90% of cases that are mostly predictable, you can use blockchain for greater human efficiency. You can think of it like an impartial robot that arbitrates human interaction.
This efficiency is also extremely important for companies building apps with human interaction. If any of these built in capabilities of the arbiter robot are desirable, you can save time and money by building on blockchain instead of building those features yourself.
If you had an arbiter overseeing your business dealings in real life, you wouldn't want them broadcasting everything you do on Twitter or anywhere else. You would expect a certain amount of discretion even if you're not doing anything illegal or embarrassing.
Transactions on blockchain are publicly visible, but this helps to ensure security because anyone can verify that the network is behaving honestly. Despite your transactions being public, your identity is not. Your privacy is maintained through anonymity.
You are free to use blockchain networks however you see fit. Any "normal" non-blockchain app can't say this with 100% certainty. You can be censored, shadow banned, or the company who owns the app can be forced to submit your data with a warrant. On blockchain, you are the only one in control of your data.
Does that seem valuable to you?
P.S. While blockchain doesn't prevent criminal behavior, it tends to be easier for law enforcement to put evidence together against you once they've de-anonymized your accounts.