this is definitely not how the future will be
To understand what a tier 3 bodyguard is, first you have to understand what the not-too-distant future will look like.
Robots will do almost everything. The only thing that humans will be responsible for, and this will be done by a very small percentage of people, is to make laws and implement other social decision-making. All jobs requiring any type of manual labor will be done by the robots.
This leaves the majority of humanity with plenty of free time to pursue leisure and cultural activities.
The downside is that the vast majority of people will earn the exact same amount of money. Humans being what they are, this will result in a large number of people making crime their primary leisure activity.
To counter this, the small number of people holding more profitable careers in government will begin to hire bodyguards. As this new profession grows, the only one that robots don’t do, even the bodyguards begin to get bodyguards.
And then those bodyguards will get bodyguards.
When a car arrives at a destination, the tier 3 bodyguard will get out and scan the area for any signs of trouble. Once he is confident that there is no discernible danger he will open the door for his employer; the tier 2 bodyguard. The tier 2 bodyguard will then do the same. When he is satisfied, he will open the door for his employer; the tier 1 bodyguard. Finally, after confirming that there are no threats in the general vicinity, he will open the door for the important government official.
When they enter the building they will repeat the procedure for every new room they enter.
Relationships will become more difficult as even an intimate dinner at a restaurant will involve at least four or more diners.
Of course there will no longer be any team sports. The logistics would make it impossible. As it is, a simple game of doubles tennis would nearly fill the venue with family, friends and their bodyguards before they could even consider opening it up to the large number of people who would want to attend to kidnap the tennis players and hold them for ransom.
(I could have sworn there was a d in ransom. In the future there will be.)
Eventually everyone will either be categorized as an important government official, a bodyguard or a criminal.
A few generations later they will build robots that can protect people with brutal efficiency and then society en masse will be forced to pursue strictly cultural pursuits. The robots, in an attempt to quell the disquiet, will suggest reading Michel de Montaigne or Blaise Pascal.
It will not end well.