Sepends what you mean by "psychotherapy". But I'd say -
1/There are lots of models and no model works well for everyone.
2/If you're going to tell someone your shit, you need to find the right person. If you cannot connect to that person or feel comfortable talking to them, it is not your fault, it is a basic human response. Unfortunately, it may not be possible to pick and choose despite this being important.
3/A good therapist should be like a real person who talks straight and if they start bamboozling you with psychobabble they're a twat.
4/It can be very difficult to find good therapy because GPs often only offer time limited counselling or CBT with enormous waiting lists. There are some charitable outfits, often at least part volunteer run, depending where you live. Some areas have much better provision than others. But like with everything funding is being cut.
CBT is especially popular as it's 'evidence based' - really it's just had more research than other models (and it pitches itself as quick) but is probably made out to be more effective than it actually is.
5/That's assuming "psychotherapy" in it's broadest sense. If you want transactional analysis specifically or something, you will probably have to pay
6/If you can afford to go private, you will probably be seeing some middle class woman who believes they are the world's greatest healer used to working with women who are upset Tarquin doesn't get home from the office until after 7 or hairy legged drum circle for the animals types. Or Sigmund Freud just emerged from a time capsule. That's probably an exaggeration.
7/If you take lots of drink or drugs and are prepared to tell people about it or are diagnosed as mad it's probably easier to get it for free. Though possibly again time limited.
8/Unless it's private the person you see may well be under pressure to fix you up quick because increasingly people who work in helping services are being made to work as if people are like tins of beans coming off an assembly line and are increasingly subject to productivity targets.
9/"Psychotherapy" is a funny word. Some techniques like motivational interviewing can work really well to sort shit out, but aren't "psychotherapy". In fact, person centred counselling, MI and solution focused brief therapy can be good because they're non directional, have no psychobabble and are essentially about providing a forum for people to work out their problems for themselves. Though counselling can be guilty of attracting those described in 6/. Discretion is advised.
10/Conspiracies about Tavistock have no basis in reality that I can find.