try adding layers to layers. for example: if you have 5 components that are in similar situations in your assembly, put there component layers on assembly layers. you can then blank all 5 at once, instead of 5 one by one.
or, another idea, assemble your master assembly with sub-assemblies. this is the best way, and the easiest.
If the datums are already on layers, go to the top of the Layer Dialog box, select Show from the pull-down menu, check Layer Items, and then go to the component you want the datums off and turn them off.
This is one of the advantages of using a standard layer naming scheme. You can have Pro automatically create layers for different entity types-- in this case, datum planes-- either by creating a default layer type for datum planes in your start part (or default template) or by using the config.pro option def_layer in your config.pro (or config.sys) file. What this does is automatically associate the datum plane with the layer of your choosing.
And in assembly mode, layers with the same name are grouped together, so with a few clicks you can blank all the datum planes of all your individual components.