How is it any people cannot put themselves in that place with imagining? Even animals could identify with what would not be desirable. Humans should have the sensibility to know they would not want what the animals being used are put through, we can likewise choose to not have anything to do with that, and we can already find out ourselves that there are ways to be very healthy this way without products from animals. And the same amount of use of resources for it and contribution to damage to environments with loss of species does not need to be continued then. https://healthyaging.emory.edu/could-eating-30-plants-a-week-be-the-answer-to-better-health/
You already got some good answers for the rest, but this part is also questionable. Lab animals tend to be kept in better conditions than most farmed animals. And while toxicity tests are terrible (esp the ones for cosmetics) they don’t tend to last as long as intensive farming. Chickens in factory farms can barely move, some collapse under the weight of their own muscles, 70 to 80% of them have broken bones. It is trully hell and that’s just one example.
Also when you look at the numbers, proportionally eating animals is a way bigger issue. Most meat eaters would be “responsible” for the killing of around ~100 animals a year just for food. For medicine, proportionally it would be way, way less, since the test happened only once.
To be honest for me veganism is not a set of rules, it’s a way of looking at things. Taking into consideration that animals are sentient beings and being honest to myself about the implications. Also on how my actions impact the world. I can’t justify not taking most medicines if I need them. However I also can’t justify not making the effort to look for cruelty-free cosmetics.