Someone made a supercut of all the footage of the Autobots and Decepticons actually battling each other in the first three of Michael Bay's Transformers films. It's a nice highlight reel, but the real story is this: These movies contain less than 5% of giant robot-on-robot action.
Don't believe me? Let's do the math. Here's the movies' run times:
• Transformers — 2 hr, 23 min.
• Transformers: Revenge of the Fallen — 2 hr, 24 min.
• Transformers: Dark of the Moon — 2 hr, 34 min.
That adds up to 7 hours and 21 minutes, or 441 minutes. Now, divide the 19 minutes of Autobot/Decepticon fight footage by the trilogy's entire run time — 19/441 = 0.043 — meaning the footage above only accounts for 4.3% of the entirety Michael Bay's first Transformers trilogy.
This... seems just a touch low to me, but you may of course draw your own conclusions.