In the old days, there were laws called “Rule Against Perpetuities” which meant trusts had to eventually end—usually around 90 years. But several savvy states decided that approach was too much “giving back” to the government. They abolished those rules, allowing a trust to live, theoretically, forever. And many more states have since joined this party as they all compete for trust assets.
Estate taxes are technically a “transfer tax”. Meaning you pay that tax every time the assets are “transferred”, i.e. passed on to the next generation. So over time these assets could be severely diminished by a substantial tax at each generation.
In layman’s terms, a Dynasty Trust is a forever trust. You put assets in today, and it stays there for your children, your grandchildren, and your great-great-grandchildren and beyond. The beauty of the Dynasty Trust is the avoidance of the transfer tax. It bypasses this tax at each generation’s passing.