Let's look at a standard song today and the number of bars and how they are arranged. The song "Misty" has 32 bars in it. Your Standard American Song book Song in general. The grouping of the "Bars" are the following: 8, 8, 8, 8, The third "8" being the bridge. This form is usually called AABA. The grouping of bars are symmetrical. But the melody can flow through time at a different pace.
Now let's look at a song which is performed by Josh Groban "When You Say You Love Me" its bar groupings are quite different. It has a total of "61" bars. Its grouping is 13, 6, 13, 6, 10, 13. The "10" is where the bridge is. These grouping of bars are asymmetrical; and, the form is ABABCB. "C" is where the bridge is - Quite a different set up, to say the least.
So, my point is this. We have come full circle from the past in the writing of songs. And by the past I mean the Renaissance. From the Renaissance to our present day the structure of songs, indeed, pop songs in particular have become more like "Art Songs of the Past!" Very exciting!!