I read a lot of anger and indignation.
Reality can be very frustrating, but assigning evil intentions to employers will not get us any place good.. US vs THEM...
Don't forget that every THEM was a US in the past and there are humans on the other side too, not heartless monsters.

I don't know what exactly you have experienced, and maybe you did meet some very messed up people, but some of these facts can be explained without any need for evil intentions...
1) When you get over 100 CVs per week or more you cannot possibly reply with a personalised message to each one of them. There is never enough time for that. That is the unfortunate reality. When you get an automated rejection message soon after you applied this means that your CV convinced the hiring manager or recruiter that you will not be a match. An automated rejection message months later probably means you stayed in the "maybe" category for quiet a while but that the company started moving forward with other candidates that seemed to be a better fit. If you had an interview, yes you should get a personalized message, a lack of one is bad form.
2) Yes, layoffs can happen all of a sudden. And no, this does not necessarily mean you had it coming and that they did not tell you because they are sadistic.. No human with a heart likes to fire someone. Layoffs are a sign of failure: either on the employer's side (e.g. the company is not making as much money as expected), either on both sides (employer and employee did not find a way to successfully work together) What matters is understanding why.
3) The many interview steps: isn't it better to try to make sure that you hire someone who will be a fit than hire "anyone" just to let them go a few weeks later? Don't you also want to know the company better before deciding to join or not? Will you be convinced after just one interview? The whole point of the long hiring process is to avoid mutual disappointment. (Or worse, imagine you move to another town for a job only to be let go soon after..)