First of all, I believe the word for this is "Bruceploitation" and you can't walk into anything with a "sploitation" at the end of the genre title with expectations of things like production value, or great special effects or a decent plot.

Mostly movies like this are void of those things and in the rare times that you actually get them they should be viewed as an added bonus.

Technically speaking, the film is a train wreck, it looks bad, the writing is horrible, and the dialogue largely stinks...

...but all of that adds to the charm and ultimately what you have is a very dated and extremely entertaining piece of crap that will hold your attention throughout, even if it doesn't hold any nostalgia for you.

No Retreat, No Surrender falls firmly into the "so bad it's good" category of films and the ghost of Bruce Lee only adds to the entertaining horribleness of the overall film.

It could be far better, sure, no one is arguing that, but if it was better it wouldn't be nearly as entertaining to watch.