One parent English, one parent Irish. Half my life lived in each country.
I didn't know anyone religious outside of the cultural sense
I knew no one called Mary
I've never been in a house that burned turf
I've never been forced to have tea
Nearly everyone I know arrives at the appointed time
I've never known a jingoistic racist
I've known many very warm and inclusive English people
English people have had greater openness and diversity in terms of race, but less in terms of class in the corridors of power. Brexit seems to have been orchestrated by old Etonians and targetted towards the other end of the socio-economic ladder (who'll pay the price).
IN MY EXPERIENCE:
Irish people are warmer, and funnier, and familes tend to be closer into adulthood.
English people are more career focussed, work is more important than leisure time.
Irish people don't 'love' funerals, they are more accepting of death as a part of life.
English people aren't repressed or stultifyingly polite, it's a stereotype that can only be applied - if at all - to a small strata of society
Class is less of an issue in Ireland, it's much more of a meritocracy.
British people - the English especially - seem to have a more rigid sense of fitting in and where there place in society is, probably related to the old class system. I think they do better in the service industries in many ways.
English people are more acutely aware of their history and heritage in terms of art and architecture, and have been more active in preservation than Irish people were (until the last few decades, I'd think)
Irish people are optimistic. Whenever disaster strikes the attitude is usually 'Be grand'. It can be so endearing, and very frustrating, take your pick.
There are marked differences between the culture of city life in Ireland and rural life or small town life. Twitching curtains are a reality of life but that's equally so in both countries.
Food is better in Ireland. Small farms producing carefully overseen products that have less miles to travel means that Irish farming tops the more industrial level farming in the UK.
Transport is better (generally) in the UK, but horrifically expensive in both.
I love Irish people, I can spot an Irish person a mile off and it's usually because they're chatting to someone animatedly. The Irish use of idiom and wider vocabulary is impressive, and people love to talk and laugh and get to know new friends. You're only a stranger for five minutes.
English people are reserved and measured, less likely to be impulsive or driven by emotion. All those things are good - and bad - depending on context.
I love English people for the reliability and stoicism, and I genuinely think that these superficial differences are nothing compared to the vast swathes of similarities of the two nations. When I'm in Ireland, I miss England and when I'm in England I miss Ireland. Different people but with fundamental similarities and the most endearing trait of both peoples is the easygoing way they have with each other.
Stereotypes are often outdated and insulting, but all the nice ones of both nations are true.
In my experience, of course.