That isn't the situation people were in when they signed their mortgage deals. You are saying people (and it will be a huge number of people) should be punished for things that weren't in their control. Mortgages were stress tested at (I think) 3% which means you would only be approved if you could afford your mortgage if the interest rate rose by 3%. Interest rates have increased 4.5% in 3 years which is above the stress test and then that is being made worse even further by inflation being over 10% in multiple years and wages not being anywhere close to keeping up.
You are saying someone shouldn't be able to live beyond their means and that is true to a degree but what the reality is is that people weren't living beyond their means when they made these decisions. They were comfortably within their means. What their means can buy them has changed, not them. What they could afford comfortably 2 or 3 years ago is now a real struggle for people. Did you agree with the energy price cap or should people have just lived within their means and sit in the dark and cold in their own homes? Help should be provided by governments when things go wrong so badly that you can't have predicted them and it will cause severe turmoil for people (and the economy).
I bought a new house in January 2020. A lot has changed since then. I've still got nearly 2 years until I have to remortgage so hopefully things will have settled down by then but are you really saying people in 2018 should have expected a pandemic, a war in Ukraine, energy prices quadrupling, inflation at 14%, interest rates being 10x higher etc.?
I do agree with you on the length of mortgages being available but you've got to look at it the other way around as well. People have done very well out of interest rates falling which they wouldn't have done with a longer fix so people probably wouldn't take a longer mortgage anyway. It also makes it more difficult to move house. What should be done is that economies should be run more competently and things should be more stable so we can make those decisions so a good or bad decision is a £100 monthly swing not a lottery win or losing your house.