Just a few years ago, big Windsor knots were the rage, I personally did not wear them but there seemed to be a horde of men, young and old with ill fitting suits that felt the big knot compensated for the fit of the suit. I remember walking into a conference and it seemed like all the men were wearing ties with big knots and I mean old and young alike.
It goes to show that many are still driven by trends.
See the image below:
I am partial to bow ties myself, but I still see many men wear big half and full Windsor knots. Much of it has to do with the fabrication of the tie, some of the cheaper ties are made from Dacron and Rayon, which can account for its thickness. Better made ties are often fabricated in natural fibers like cotton, silk, linen and wool.
There is also the amount of backing in some ties that can produce this knot as well as where they begin to fold the tie, some prefer tying closer to the wider angle of the tie which can also produce this type of knot.
Normally the six and seven fold ties are unlined and made from large swatches of silk and accordion folded to produce a rich and luxurious tie with weight that does not twist when making your knot of choice these depending on the designer can also produce larger hefty knots. Many designers today have switched to a doubled four-folded design that is backed and lined and referred to as a seven-fold tie, I think Kiton and Brioni use this process.
Whatever the case, what we are seeing is a return to smaller knots, like the oriental or the four-in-hand as well as smaller half and full Windsors. This is attributed in part to ties that are designed with less and better quality fabrics. See the images below from Paul Stuart:
We can see a return to a more clean and refine look that was once common among men of good taste. By the way when I wear a regular tie I preferred a small four-in-hand knot.
In the meantime remember that fashion can be cyclical, your best bet is to stay slightly conservative and wear classic clothing that has stood the test of time. Yes you can play with colors and patterns but the clothes should be quality made pieces that will look good and still be in style 20 years from now.