Airlines that take "cadet" pilots usually have a significant input into their training and early development. At this level, few are interested in anyone that falls outside of this criteria.
Experienced pilots are likely to have significant and relevant experience from either a military or commercial background. It is here that "500 hours on type" as a minimum level of relevant experience is sometimes stipulated.
For an airline that is a TRTO, providing a type rating and subsequent line training isn't particularly problematic, and in the case of low experienced pilots "cadets" most would regard it as vital.
Even when recruiting experienced pilots, the background and acquisition of relevant experience is an important factor. There is a great deal of resource, and companies can (and are) choosy about the type of experience they are looking for. There are factors that can be real "red flags" when it comes to background. I am afraid that a lot of these "opportunities" fall into that category.
Quality companies expect quality candidates. They want training that falls within their own definition of quality (and that is usually their own, or a company they acknowledge as providing same.) Less quality companies, are likely to be deriving income from this form of training, rather than seeking employees who have already availed themselves of it. Obviously, this is a reality you are now becoming aware of.