The 1992 tube stock is different to what was done to the BREL / Brush 465/0 & 1, neither of which is shown in the video.
The video mentions the retractionings of the 1992 stock but doesn't actually show it, the main (only) visual topic is keeping the existing traction equipment working. What is shown in the video is knackered existing DC traction motors (with commutator flash over damage) being taken off to be sent away for rebuild, and refurbished existing DC traction motors being refitted - this is what LU and 3rd rail EMU operators have been doing for over a century (same applies to the DC traction motors on older Diesel Electric locomotives).
Nothing about the new traction system is visually shown in the video.
One of the advantage of the three phase asynchronous "squirrel cage" motors is they don't have commutators so are much less prone to catastrophic failure (they are also more efficient, smaller lighter). You can't show commutator repairs on motors that don't have commutators!
In the medium term those motors in the video will either end up as Waterloo and City stock spare parts float or scrap.
I terms of "3 phase retractioning" of rolling stock there are two different sets of circumstances that have occurred in the UK:
a) On rolling stock already with three phase AC traction motors, the replacement of older (GTO) inverters with new (IGBT inverters) [cheaper, quicker, easier]:
- BREL / Brush 465/0 & 1s - Original ABB GTO inverters replaced with Hitachi ones (Hitachi wanted to learn the nuance of electrical interference etc in the UK before doing new build with the 395s), motors not replaced
- Most Eurotunnel shuttle locomotives (91xx) - Original ABB GTO inverters replaced with new ABB IGBT ones (retrofit solution developed for Eurotunnel and CFF who had locos using the same GTO inverters)
- GBRf Class 92 - Original ABB GTO inverters replaced with new ABB IGBT ones (used the same original inverters as Eurotunnel 90xx) using the "off the shelf" solution ABB had developed for Eurotunnel and CFF.
b) replacement of the entire traction electrical system (DC traction motors or single phase non variable frequency AC and downstream of the transformer in the OHLE case*) - new motors, initial fitment of (IGBT) inverters and completely new control systems including WSP [more expensive, more involved and time consuming].
- SWT/SWR 455s,
- SWR 442 (never entered service post rebuild)
- Anglia "Renatus" 321s*
- 1992 tube stock
- SWR 484s
Outside of TfL most of the rest of the industry uses Associated Rewinds in Dublin for motor repair and they have a few good animations on the website.
https://associatedrewinds.com/index.html
(Mostly locomotive motors (much bigger) shown in the photos e.g. Class 66, 59, HST power car, 70, Traxx)