I don’t think it is a question of ‘how much weight’….do you train the whole body? Are the core muscles engaged?
My rule of thumb is: the more I want to do, the more I need to train all the muscles so I can do it.
Which would translate in: the more weight you want to lift as part of your exercise routine, the more overall training you need to put in upfront e.g. with the core muscles…
I consider this rule true whether you have an hernia or not…again we all age, so we all have some physical problems. Even the professional athletes (even in their prime) may have some cartilage problems that have not manifested yet: you train your body as if your (sports) life depended on it.
Do this and it does not matter anymore how much you can lift (my 2 cents:)