The only people who have a problem with carbomer are the organic sector. Carbomer is not specifically banned by the Soil Association, but they do require that natural thickeners be used when they are suitable. They usually are though they aren’t as good. I think this is probably the single biggest reason why organic products often seem a bit rubbish compared to conventional ones. They do the job just as well, potentially at any rate, but they just lack the elegance that can be achieved with carbomer. But that presumably is a choice that the people who seek out those kinds of products have made.