Stretching is great on paper but in practice it doesn't often do much good, usually because people misunderstand the application.
Static stretching will provide temporary relief from tight muscles, this much is certain, but unless you're addressing why the muscles are tight, it's missing the biggest piece of the puzzle.
If you've got weak/inactive glutes, all the hip stretching in the world isn't going to fix your tight hip flexors, and if your mid/lower traps are weak then your rhomboids are going to be a fibrotic hell hole, and it's going to take way more than just a pec minor stretch to take care of that.
IMO, strengthening the weak muscles will do more than stretching, although obviously you would ideally do both.
It's also the case that a lot of times people just stretch what feels tight without giving much thought to why they're tight, which can do more harm than good. Most people feel they have tight hamstrings, so they stretch them. What they don't realise is their hamstrings are only tight because their pelvis is in anterior tilt, pulling their hamstrings into an already stretched position. Stretching the hamstrings only exacerbates the problem. Same with the lower back; it feels tight so people stretch it, but the reason it's tight is because the core is weak, and stretching it actually makes it worse by encouraging movement at the lumbar spine, rather that the hips.
A little experiment to prove what I'm saying. Without rounding your back, try and touch your toes. If you can't, do 3 sets of bird dogs with a nice slow, controlled tempo, and try again...