Yes, this is normal. Any unevenness in light output – what we affectionately call "the ring effect" – is an inherent aspect of this type of our vintage ceramic-style coated Classicolor bulbs.
Lighter and darker areas (especially at the tip) are related to the variations in the distance of the glass shell to the light source (the LED filament). The effect is more apparent on some colors than others and you'll see this with both Tru-Tone LEDs as well as the classic incandescent bulbs that Tru-Tone are inspired by.
If, however, you notice issues with an individual bulb appearing more dim than it's neighboring bulbs, that may be indicative of an issue with that single bulb rather than any normal variations in light output across all bulbs on the string.