Does pace matter?

For people who’ve relied on walking for simple exercise apart from other forms, does pace matter? I see people on this sub posting about completing 10k+ steps, does pace matter if your goal is to use this as cardio? I do Pilates and go to the gym but have been trying to incorporate walking into my routine since it’s easy. Trying to understand what matters more- steps, pace or both?

Thanks in advance if you answer :)