A common misconception is that back pain is caused by a weak core. I was taught at uni that back pain was more likely in people whose transverse abs didn’t activate before they moved, and as such we had to re-train this by giving people isolated transverse abs activation exercises.
I haven’t done this in at least 5 years, and the evidence no longer supports this theory. The idea that you can activate transverse abs in isolation and that this is in any way relevant has been debunked.
Moreover, there is strong evidence that core stability training is NO more effective than general exercise in chronic low back pain management.
Many people hurt their back while sitting, or bending over to tie a shoelace, or something else innocuous. The idea that this is because their core is weak makes no sense.
There are times it may be more relevant eg sport or heavy lifting but it’s rarely as simple as a “weak core”; often lacking capacity for the movement generally, among other things.
What to do instead? General exercise that can be tolerated has GOOD evidence in low back pain. Find what you can manage and do that 👍🏻
Reference: Smith, B. E., Littlewood, C., & May, S. (2014, 2014/12/09). An update of stabilisation exercises for low back pain: a systematic review with meta-analysis. BMC Musculoskeletal Disorders, 15(1), 416. https://doi.org/10.1186/1471-2474-15-416