Even wealthy in the US tend to have much less servants than they would have in the past. Labor is too expensive, and the large middle class has made automation just as good and sometimes better. Sure I could hire someone to turn on my lights - but the switch on the wall works well and isn't much effort (compare to the lamp lighter of the past which did work that would be annoying).
Note, I and, I assume, the parent commenter weren't talking about home automation.
"Virtual personal assistant" to me meant a computer program that could understand speech and carry out a limited set of actions based on that speech - the computer equivalent of a human personal assistant/secretary.
That has been getting much less common. My dad used to have "his secretary" do tasks like schedule is meetings and book travel - the secretary was a department secretary for a couple dozen engineers and was kept busy just serving those needs. Today I don't have a secretary for several hundred engineers. My computer is better at scheduling meetings than the secretary ever was. Go back 100 years and the rich would have hard far more servants than they would today because various levels of automation have replaced many jobs.
The right still have servants of various types of course. Right now "Virtual personal assistant" are too limited to replace humans. Since I cannot afford a human servant I'm hoping that changes. Time will tell.
I would love a virtual assistant that could handle the tasks a human personal assistant does. VA would be available 24x7, would perform consistently regardless of time of day/how long they've been running/awake, would know/ understand my particular habits/preferences.
Maybe there's some bespoke software firm that does provide such a service for rich-enough people. Of course it'd have to run mostly locally/on-premises - none of this cloud stuff/monetizing my behaviours to bump their revenues.
The rich can afford humans to do this job. While a lot of the jobs the assistant does would be easy to automate, the hard part is from the vague description of what they want to getting something acceptable. If I ask for "famous singer" do I need that singer, a cover band, or any band in that style, any live music, or a good DJ - depending on the situation any might be acceptable (and sometimes several of the above are not available at any price). Scheduling just the famous singer is easy - just send a calendar request and see if they accept (it is more complex than that, and odds are the singer isn't signed up for this service, but that is all details), but trying to figure out which substitute is available and acceptable is hard.