The maps sdk will utilize all CPU cores to make things as performant and responsive as possible. If you pan and zoom a lot, a lot of tiles could be downloaded and processed which can create spikes (especially on a fast internet connection). This is normal. On a slower PC it is still smart enough to know that if you already panned past a tile that didn't get a chance to get processed, and it'll skip it and move on.
One thing to note though is to make sure you're not running in software rendering mode - that can often happen in remote desktop (except with .net9), WinForms embedding, or on some VMs or low-end GPUs and that'll put a lot more pressure on the CPU instead.
If you want the most performance possible, WinUI uses a newer DirectX technology than WPF and integrates much better with Windows' rendering stack and is therefore able to squeeze out more rendering performance with less resources (and also suffers much less from the software rendering fallbacks mentioned above).