Not necessarily. It depends on how comfortable you are divulging personal information about yourself to the sb and vice versa. Just because your having sex with her doesnt mean she needs to know everything about your personal life. When going on dates and booking hotels (if that's something you have to do) there are ways to be discreet about it. Obviously there is always a risk to get caught either with an sb or an escort but after a while you figure out ways to better cover your tracks.
There’s a more concrete boundary of communication with an sp. Especially with an agency to mediate. For both sides. There’s no blurring. Theres no risk of messages at odd hours. It’s a set time and place and then daydream in between. No overcoming of emotions and doing drastic out of character moves that gets ones spouse catching on.