I've seen this sentiment expressed a lot by Hindu Nationalists, and while I understand its a comforting thought for them, it is not true. Mughal domination of India was shattered by the Persians, the Marathas were simply the most adept at picking up the pieces.

Most of the Indian Subcontinent was not under the control of the Marathas, when the British began their formal conquests.

Keep in mind that the Maratha hold on many of their regions was extremely nominal. They could not martial many resources or support from Orissa, Chhattisgarh, much of Madhya Pradesh, or Rajasthan. The different wings of the confederacy were often hostile to each other.

The Marathas before their defeat by the Afghans at Panipat were a serious threat for subcontinental domination. The Marathas afterward were still formidable, and likely the single most powerul polity, but a shadow of what they were.