two points here
1- there are awesome things to buy on HKEX and it’d be awesome to have it in T212 and there are several requests for this to happen in the past here (including myself) if your reason for requesting HKEX is this , hurray!
if your reason for requesting HKEX is this no dice
2- HKEX being available to trade on T212 will not change much about the recently un-ISA-eligibified stocks like TSM or NIO. HMRC only recognises main board from HKEX, cross listed shares (like JD.Com) or shares listed in minor boards like GEM still won’t be avialble. If any of those 90 shares removed from ISAs were listed on main board of HKEX, there would not be a problem in the first place, regardless of HKEX availability on T212 or not.
for example if you look at JD listing https://www.hkex.com.hk/Market-Data/Securities-Prices/Equities/Equities-Quote?sym=9618&sc_lang=en you’ll notice it is a Cayman Islands incorporated stock, that is listed on NASDAQ primarily. so can’t go into your ISA regardless of where its bought from.