The answer is, it depends.
Whilst pelvic floor exercise has Level 1A evidence for treating mild-moderate stress urinary incontinence, as well as mild-moderate bladder and / or uterine prolapse, there are many symptoms or pelvic floor syndromes that may not benefit, or may worsen with just doing, or doing excessive pelvic floor exercise.
Like all muscles in the body, the pelvic floor needs to be able to contract, AND relax to function at its best, and stave off problems like pelvic pain, incontinence, vaginal heaviness or pain during intercourse, and of course, to have the ability to orgasm.
Our pelvic floor is broken up in to multiple layers, - some superficial, and some more deep. The superficial layers of the pelvic floor have function in surrounding the orifices - in particular the urethra (where urine exits the body) and the anus - (where we excrete feces from) Whilst not all of the “closure” function of these orifices is from muscle under our voluntary control (much of the control is via what we call smooth muscle, which is controlled by our autonomic, or “automatic” nervous system and therefore is not in our conscious control) - the superficial pelvic floor muscles still do play a supporting role.
Particularly for vaginal penetration, and a “normal” defecation action - these muscles need the ability to contract, and relax and do so in the right order, or synergy.
So for someone who has pelvic pain, pelvic hypersensitivity, pain on penetration, (particularly at the entrance of the vagina) then kegels may not in fact be the answer at all. Symptom relief may rely in finding a knowledgeable heath care practitioner, such as a trauma-informed pelvic floor physiotherapist, and focusing on relaxation, mindfulness and stress relieving exercises. Check out this post on 'Do Kegel Exercises Always Help', as it has some great alternatives and stress relieving exercises.
Equally, it is entirely possible to suffer from bladder leaks in part because of a pelvic floor that does not need “strengthening”, OR needs both strengthening, and relaxation (confusingly, you can have a “weak” but “tight” or “too high tone” pelvic floor that lacks the mobility it needs to go through full range of motion - strong contraction and lift, and full relaxation and descent.
As with any pelvic floor or bladder symptoms, it is recommended to speak to your health care professional for any new or persistent symptoms.