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Under  FCC statute  ( USA  )  and EU statutes ( and many other countries standards regimes )   -  any device that is an unintentional radiator is subject to EMI limits  and more especially if it interferes with legitimate comms  -  whereupon it can be ordered to stop by the FCC  ( and fined if they so wish )

So it is generally a good idea to see if any device you design or cause to have made  -  is reasonably quiet

Having said that   -  you refer to LT-spice sim of a filter  -  have you put in the R  & C for the chokes ?   and the R and L for the caps  ?

in the real world  ( IRL )  these parasitics  ( and pcb layout ) generally give you different filtering than you expect,  with peaks and dips in the attenuation curve

using a cheap VNA to spot this is a good idea