What is the difference between .filterMetadata(), ee.Filter.lte() and .sort() in google earth engine?

Question

I am currently trying to obtain images that have less than 70% cloud cover (for example) and I have come across multiple variations of the same. Could you tell me what is the difference between these three approaches and which approach might be most suitable for obtaining a set of least cloudy images?

Approach 1:

var collection = ee.ImageCollection("COPERNICUS/S2")
  .filterBounds(geometry)
  .filterMetadata('CLOUDY_PIXEL_PERCENTAGE', 'less_than', 70);

Approach 2:

var collection = ee.ImageCollection("COPERNICUS/S2")
  .filterBounds(geometry)
  .sort('CLOUDY_PIXEL_PERCENTAGE', false);

Approach 3:

var collection = ee.ImageCollection("COPERNICUS/S2")
  .filterBounds(geometry)
  .filter(ee.Filter.lte('CLOUDY_PIXEL_PERCENTAGE', 70);

Answer 1

Approach 1: all images in the collection within bounds that have less than 70%

Approach 2: keeps all the images within the bounds, but sorts them by descending order (most cloudy first)

Approach 3: all images in the collection within bounds that have less than or equal to 70%

However, between filterMetadata() (A1) and filter(ee.Filter()) (A3) the result is the same. The docs to this.filterMetadata() shows that it is equivalent to ee.Filter()