Being able to add / remove components then query based on component sets an entity has is an important part of ECS data driven design, which Unity is trying to

Being able to add / remove components then query based on component sets an entity has is an important part of ECS data driven design, which Unity is trying to move to with eg. DOTS. Just leads to less branching etc. once your data is prepared. I'd rather just have my code express expectations upfront then query the entities that match, vs. needing to handle a combinatorial explosion of if/else based on existence checks.