Worst part is, the effectiveness of Pfizer and Modurna are still in question in regards to the delta variant. They seem to work, but not quite as good, but not really sure and waiting for more data to come in.
According to the UK government, against the delta variant, "Pfizer-BioNTech vaccine is 96% effective against hospitalisation after 2 doses". This is "comparable with vaccine effectiveness against hospitalisation from the Alpha variant."