It is indeed unusual for a blockchain project to remain in the "Enclosed Mainnet" phase for years after having a massive user base.

Here are some logical and technical reasons why Pi Network seems to be very slow in completing KYC matters until token distribution:

1. Scale Issues (Massive Scale)

Pi claims to have more than 50-60 million active users. Verifying the identity (KYC) of tens of millions of people globally is a huge logistical challenge.

Self-KYC: Pi is building its own KYC solution because the cost of using third-party services (like Jumio or Onfido) for 50 million people would run into hundreds of millions of dollars.

Document Variation: They have to validate thousands of ID types from nearly every country using AI and local human validators.

2. Strategy "Enclosed Mainnet"

The Pi Core Team intentionally locked the ecosystem to prevent dumping.

Price Stability: If tens of millions of people suddenly receive tokens and dump them on exchanges simultaneously without any utility ecosystem, the price of Pi is likely to crash to zero.

Gradual Migration: They chose to move balances to the mainnet wallet slowly to ensure the network remains stable.

3. Focus on Utility, Not Speculation

Unlike other coins that immediately list on exchanges for trading, Pi insists on building its internal ecosystem first.

They want Pi to be used for purchasing goods/services in their own app before it can be exchanged for Rupiah or Dollars. The issue is, building this app ecosystem takes an incredibly long time.

4. Ad Business Model

Some critics argue that this delay might be a deliberate business tactic.

Ad Revenue: As millions of people still open the app daily to "click lightning", the Core Team is raking in significant ad revenue. There's no pressing incentive for them to rush into the mainnet if the current status is already financially rewarding for the developers.

5. Regulatory Compliance

Due to its global user base, Pi must deal with anti-money laundering (AML) regulations in various countries. Mistakes in the KYC process could lead to this project being shut down by international financial regulators before it even gets a chance to grow.

Conclusion:

This delay is a mix of overly ambitious technical goals (wanting self-KYC), fear of price crash if launched all at once, and a business model that still profits the developers during this wait phase.