Well done to the OP for sharing their experience, which is valid even if it’s not the same as that of others and doesn’t show BA in favourable light. Sadly, any perceived criticism of BA isn’t always well received in these parts, even if valid, constructive and well considered.
I can identify with a lot of the points raised. I’ve also had some really excellent flights in CE. I think the main point is that when BA is good it’s good, when it’s not good it can be awful. I find EasyJet more consistent. They are explicit about the number of bags the cabin scan accommodate and enforce their priority boarding. I understand some find service recovery poor on EasyJet but I received full EC261 compensation for an obvious tech cancellation within a week, while BA took 4 months, several back-and-for the not addressing all points, and escalation to the Executive Office for barely satisfactory resolution.
I don’t live in London so I’m fortunate to have multiple options. BA work well for some trips, EasyJet and others are options for some, and there are many other options for long haul which are increasingly attractive as BA changes it’s offering. I choose based on a balance of cost, perceived reliability, and much less importantly recently, status benefits, holding BA Silver and Virgin gold.
I understand many here hold BA in high regard and have had consistently excellent experiences. That doesn’t make the OP’s experience less valid. It’s good to discuss with respect for others’ opinions but please don’t dismiss them out of hand as their experience wasn’t the same as yours.