One of the weirdest of sayings-
Entertainingly appropriate!
The second real arcade monitor I encountered intimately actually had this style of tube grounding.
In fact, of the four legit monitors I now have (not the Franken-screens I am forced to try to build out here) three of them use this method.
One is a 25" and two are 27"s.
Now that I look, even one of the 27" consumer tubes I have to try to convert uses this style.
Not sure if it is something later gen or more so that Panasonic decided it was a good plan (many people here with more wisdom than I- maybe someone will see this and comment.)
All of my 19" tubes actually use the braided wire/spring technique so I can't say for sure.
For reference, picture here is a tube out of one of the RUSH 2049 cabs that originally had a Sharp Image 727 chassis (which has been swapped out for a functioning Hong Eun.)
Think of your monitor as its own little island in your cabinet which needs a ground connecting tube, chassis, and neck board.
Different manufacturers had them connected in various places in different ways so just check that you are covering the bases for your model items.