it has no drawbacks, 99% of every PC part has some sort of safety feature built in so you cant break your computer unless you go out of your way to
Game analysis/review uses 100% cpu power

Using any component or system at 100% capacity, even for short durations, can potentially cause some damage. While short bursts of high usage may not immediately result in significant harm, they can generate increased heat and stress on the components.

When launching Game Review, the Analysis tab is also loaded, which includes an engine that will also load and consume resources. If you disable Engine Lines and Evaluation, that won't load during reviews.
The Reviews are run server side, so other than the progress and display, that portion of the code isn't using many resources.
Using any component or system at 100% capacity, even for short durations, can potentially cause some damage. While short bursts of high usage may not immediately result in significant harm, they can generate increased heat and stress on the components.
only temperature can damage components
I have acquired a Diamond subscription to ensure I can benefit from chess.com game analysis.
To support my gaming endeavors, I possess a robust processor: the Intel(R) Core(TM) i9-9900K CPU @ 3.60GHz. When harnessed at its maximum potential, the processing power at my disposal is truly formidable.
During my game reviews on Chrome, the processor consistently operates at full capacity, maintaining a steady 100% CPU power utilization. However, when opting for Firefox, I notice sporadic spikes to 100% CPU usage during calculations, promptly settling back to a mere 5%. This pattern persists when making moves during the analysis process—a surge to 100% CPU usage followed by a return to 5%. I am concerned about the long-term implications this may have on the CPU's well-being.
Recognizing the potential drawbacks, I have submitted a bug report to chess.com, expressing my concerns regarding this matter. Regrettably, I am yet to receive a response or resolution.
Ideally, I would prefer if the CPU operated at around 30% of its power, even if it entails a minute-long waiting period, rather than subjecting it to frequent spikes to 100% utilization.
As an alternative, I have endeavored to run Stockfish locally with various chess graphical user interfaces (GUIs). However, I must admit that I find the process somewhat convoluted, and despite its complexities, chess.com still fulfills most of my requirements—excluding the issue of excessive CPU usage.