Agree OP. Most people in GB not only don’t care about NI, they are ignorant as to the origin of the conflict.
I’ll repeat a summary I put on another thread.
The basic problem in NI is that there are two communities that in many cases lead completely separate lives.
One community - Protestant/Unionist/Loyalist - are descended from British settlers from the 16th/17th century when England invaded Ireland and displaced much of the local population. They identify as British and have a strong British identity. Some in this community place a strong emphasis on maintaining this identity - e.g. The Orange Order when simply attending a Catholic church service (even the funeral of a friend) means expulsion.
The other community - Catholic/Nationalist/Republican - are descended from the native Irish and have an Irish identity.
The two communities have never mixed and can live totally separate lives - living in separate areas, going to separate schools, playing different sports, even listening to different radio and TV.
Each community is equally entitled to their identity.
Ireland was partitioned because at the time a majority in the northern part were from the Protestant/Unionist community and did not want independence. Britain saw them as British and prioritised their needs. They split the island based on the demands of the Unionists, ignoring local wishes. Two counties which voted for independence were included in NI to make NI larger and more viable, even though the majority in those areas wanted independence.
Within NI were a minority of Irish who were - and remain - every bit as Irish as their cousins on other sides of the border. We would not say that people in Scotland are not Scottish as they do not have independence.
Until the GFA, NI gave priority to the British identity, and in many cases actively discriminated against those from a Catholic/nationalist community. To consider yourself Irish in NI was seen as subversive by the state, even though you were living in what the world sees as Ireland.
The GFA was a real breakthrough as it gave parity of esteem. People in NI could be British or Irish or both. People are entitled to both Irish and British passports as they choose.
The border was removed so that those who wanted could feel for all practical purposes that they lived in a single country and many live in NI (cheaper) and work in the republic (better wages).
Brexit and particularly Johnson’s hard Brexit has messed this all up. Theresa May’s deal would have kept the U.K. in the single market, keeping the peace process jntact. Johnson has ignored all that and gone for a hard border. This means there has to be a border somewhere - a land border is unenforceable and will upset the Irish community, a sea border upsets the British community.
So this is all a big mess. Under the GFA NI was normalising as identity no longer mattered so much. Now when people feel their identity is under threat, all the problems re-emerge.
It is not due to religious bigotry but to national identity. If you are English, consider how it would feel if the national border was redefined so that you were no longer in England but in some other country. People’s identity matters. The Irish and British populations of NI are now equal in number, and the only solution is where both are held in equal esteem and recognised as equally legitimate.