I have flown a helicopter with a Gmeter fitted - some of the Mk 7 Lynx at Middle Wallop that were used for the Blue Eagles displays - and I have flown all the display manoeuvres many times including loops, barrel rolls and back flips.
The prime area of concern regarding component life was in fact the TR - the TRGB is on a long lever away from the MRH.
A loop was generally 2 to 2.5 G depending on how smoothly you pulled up and pulled out and a barrel roll about the same; even a back flip to flyaway was under 2.5 G. The only manoeuvre that exceeded that was the back flip from hover to hover - 1000' to 700' followed by a second back flip - it was difficult to get it back to the hover at the required height in much less than 3G.
Air combat manoeuvring involved 180, 270 and 360 wingovers, almost all around the 2G mark - exactly the same as a 60 degree AoB sustained turn.
I am not giving carte-blanche to cowboy flying but a well-trained pilot can conduct some of these 'acrobatic' manoeuvres quite safely and with less stress on the aircraft than a heavy USL or flying at VNE for hours at high AUM.
Helicopters tend to look inverted even at substantially lower AoB so don't be misled by a poor quality video.