Creating a report on Powerbi.com now gives 'transform' power query option

Power BI has been gradually:

• Moving more import and modeling functionality into the Service
• Introducing deeper semantic model editing, even allowing dataset editing directly in the browser (Premium/PPU features)
• Updating the “create from file” pipeline in My Workspace

One effect of these changes is that header detection is no longer assumed during the quick semantic‑model creation path.
This is likely why you now see the two buttons and different behaviors.

Think of it this way,

Create Report:

• For quick, simple uploads
• No transformation
• No guaranteed header detection
• Fast auto‑semantic‑model creation
• Intended for clean, well‑structured files (e.g., Excel tables)

Transform data:

• Opens Power Query
• Lets you clean/shape data
• Ensures headers are correctly applied
• Gives you control before semantic model is created
• Much closer to Desktop behavior