So let's measure them. Because no matter how often that first sentence is repeated, it does not become any more true.
Measurable way #1:
How, exactly, are those spot details going to be embroidered onto any garment when reduced to a 3" area? Which line will you be removing/reworking/editing in order to achieve a logo that reproduces well at lower scales? The same holds true for the outer ear details and the tongue detail off to the side of the teeth.
With the thicker/bolder lines on the former mark, the logo could shrink down and still maintain visual integrity. This is not the case on the new mark.
Since it is functionally inferior, this makes the new mark inferior on the whole.
Measurable way #2:
With the new level of cartoonish detail - the illustrative style - when applying the new mark to playing surfaces, the fine detail work will be lost since blades of grass/synth turf are variable. When that fine detail is lost in the application of the logo, it changes the mark, and thus, makes it inconsistent. Inconsistent logos are inferior logos.
These are but a few of the measurable, quantifiable ways the new mark is inferior.
To Billy's point, the fact that a pro football team is implementing these logos doesn't automatically exonerate them from technical errors that will prove difficult for outside agencies/output houses/graphics companies/etc. to handle with consistency. Depending on where Khan went for this design, they may very well have not thought about each and every application of the mark. Or, he may have just really liked this Bugs Bunny style and ramrodded it through. I've dealt with similar phenomena throughout my time in sports logo and general logo design projects.
Regardless of the reason, the outcome is the same: A new mark that has problems in a very measurable ways.
I still think this is an upgrade for the Jags. Obviously that could change once its practical applications begin to be used, but I like it.
I don't get the cartoonish comments though. To me cartoonish suggests its less realistic, but this logo is more realistic that the old logo,