You can't stop reading the instructions after that first paragraph, "Purpose of Form."  Continue to the next paragraph:

Who Should File
Complete Form 8801 if you are an individual, estate, or trust that for 2024 had:
• An AMT liability and adjustments or preferences other than exclusion items,
• A credit carryforward to 2025 (on 2024 Form 8801, line 26), or
• An unallowed qualified electric vehicle credit (see the instructions for line 20).
File Form 8801 only if line 21 is more than zero. [Which is never going to happen unless you have a carryover amount from 2024 on Line 16.]