Also the international kit reached 133 sold in the recent Lightcycle GB.
That is incorrect, the "international kit" you speak of is actually a compatibility kit that includes Tsangan spacebars, 1.5 mods and a myriad of other adapter keys that are used in many non-standard layouts that have absolutely nothing to do with international boards. Let's say half those 133 kits were purchased with the intent of being used on UK/NORDE boards, which I know is already being generous - that's 67 rounded up, how many orders do you expect Nautilus or any other good GMK set to potentially pull if it releases on Massdrop some time next year? Let's speculate 1500 which I believe is very realistic, if a theoretical international kit were to sell 67 kits that'd be 4.5% of all orders placed.
Godspeed is the easiest comparison to draw right now but there are other older examples that tell the same tale (Jukebox, the original Hyperfuse, GMK carbon, etc.) - out of 3700 orders placed UK
plus Norde (2 diff kits) sold like 80 kits. Blank ergodox sold more than both of them individually (bare in mind there was also a regular Ergodox kit) and UK was literally the one that sold the least out of every single kit. Together they accomplished exactly 2.3% of the buy. Why would you push people to buy like 30 keys to include ISO/Norde in a base set if it caters to such a minuscule audience, that's completely irrational both from a resource as well as monetary point of view. Including it in the addons would literally double the amount of keys which again is far from sustainable in my opinion especially with GMK.
As you said yourself, if they're sold separately they won't tip so why do you wanna shove them onto the other kits and force them upon other people? As I've said just make the swap to ANSI already and put all that behind you, my wife is Finnish as well and we both just use ANSI with reprogrammable keyboards and/or Portuguese/Finnish windows language preferences, it's not like we look at legends. I understand many will probably not want to do that but then you have to deal with it and accept the fact that this is a business and like any other sale in any other area if the numbers are not there then it's not happening. Talk to Mito, T0mb3ry, Livingspeedbump or anyone else and I'm pretty sure they'll all say the same Zambumon's already stated here.