1st. Good choice of tires - they should serve you well.
2nd. If you hang around the bike industry awhile, you'll find they change "standards" every few years. The glass-half-full folks believe this is because equipment and technology is ever improving and the change reflects this.
The glass-half-empty (and it's cracked, too) crowd will tell you it's to keep us sheeple buying latest and greatest stuff to pad the bank accounts of the cynical rich.
I say don't worry about why - buy what you like and let the chips fall where they may.