I had to look up what chicken salt is and despite what it says on Wikipedia, I’ve never seen it in the UK. However, it seems very similar to something I had in Iceland called “Kartöflukrydd”, which translates roughly as “potato spice” and can be found under a similar name through Scandinavia at least.

MSG based seasonings are definitely not banned though. Maggi is very popular in central Europe and I think that is literally just MSG and salt.