It’s normal to loose ability to hear higher frequencies with age. The good news is 10 kHz and above is mainly where “air” occurs in music meaning cymbals lose their sheen and sparkle, etc but most music occurs well below that frequency. On the plus side a lot of noise and distortion that can make listening fatiguing also occurs at those higher frequencies so older ears will naturally filter that out.
Other than that, what one hears or not and what differences can be discerned or even matter will vary case by case. A hearing test is really the only way to know. The good news is that once does know and up to a certain point equalization might be applied to compensate. Modern Digital Signal Processing for example like that included in Roon streaming makes applying equalization for a variety of purposes easier than ever.