That 97 dbA figure is deceptive. It's not an absolute limit that cannot be exceeded, but rather one of several tiers that regulate how long you can be exposed to that level. While some bonehead with the EU may be misinterpreting their rules, it's probably more like someone unfamiliar with how the system works shot his or her mouth off without thinking first.
Prior to my retirement at the start of the year, I was a manager for OSHA, the United States agency charged with workplace safety and health. One of the laws that my "people" enforced was our "noise standard", and it is generally similar to that used by the EU.
Under these noise standard, you can be exposed to a level of 90 dbA for not more than eight hours during a single work day. As the noise levels get higher, the amount of permitted exposure time at that level progressively gets shorter. These "exposures" are cumulative, and any time spent at 89 dbA or below counts as exposure to a level of zero.
(There is an absolute upward limit, a level that no noise level is allowed to exceed without some protective measures. 140 dbA is a level often reached with weapons, and of course with the stoner crowd in some types of rock music. Most folks are smart enough to avoid this sort of thing.)
While a sound level meter (SLM) is a good screening tool, the only way to accurately figure exposure is to use a device called a dosimeter. It measures the level on a continuous basis and does the total computation that gives the end result. Much simpler than the manual method that we used back in the early 1970's (which required timed readings on an SLM to a strict schedule).
When a musical piece has a peak sound level up in the high 90's, it's important to keep in mind that the high readings are only part of the picture; you have to consider the entire exposure, not just one fortissimo passage.
Push comes to shove, if you find (at any noise level) that you are ending up with ringing or buzzing in your ears, you are overexposed (for your particular body's limitations). The sound levels set in these standards are only required to be protective for 95% of the total population, and there are many who are more sensitive and will be harmed even at the 90 dbA level. Use the plugs if you are in this group, and it doesn't hurt to use them in any case. You will get used to them over time, believe it or not.