Severely limited range of motion is typically not an issue with tissue extensibility. That is, it's usually not a matter of how much range the body 'can' give you, but rather how much range the body is 'willing' to give you in the moment. In these cases, those tight muscles are actively contracting to prevent being stretched, not lacking actual extensibility. If the muscles are strong and stable, they'll give you all the movement you need.
The most common reasons for muscles to be exceedingly tight are stabilisation or protection of a compromised area or movement so, these very tight muscles will typically feel strong. This strength, however, can produce force but often within a limited range of motion. They are unable to provide the fine control, balance, timing, and extensibility that are the hallmarks of real, usable strength.
Your body only gives you flexibility where there is stability. Stretching your way into a new range of motion does nothing to add stability to that new range. If you don't train it, you won't maintain it. You'd have to stretch it out constantly to keep it.
You can get a lot stronger without getting any bigger. Strength isn't about how much muscle you have, it's about how well your body learns to use the muscle you already have.