The problem with the British army (speaks an outside observer) is that the last time there was whole sale reforms was in the 1870's. That's when 90% of the regiments were established. At the time the army needed lots of units to defend a huge global empire. Now they really don't need all the regiments they have. But because many have existed for 120 years any changes are up against all the history and sentement over praticallity BS. The UK army has needed a good clean up of units since the 50's, but it's only happening now.

We have a very similar regimental system as you Brits, biggest difference is no depots. But we can disband units if they serve no purpose anymore. We make whole regiments reserve. When I was looking into joining the artillery reserve the headquarters office had a whole wall devoted ot the regiments history on it. From it's founding in the 1890's to it's role as a coastal defense unit in WW1 to being deployed to Italy in WW2.