Growing only soft fruit is not as work intensive as growing veg but there are still jobs that need doing.
Firstly the area around the fruit bushes need to be kept weed free. Both for maximising crops and ease of picking as well as allowing more airflow to help minimise fungal diseases. Raspberries are notoriously difficult to weed with couch and bindweed being the most problematic.
Secondly birds love soft fruit so you will need something to keep them off. Netting or a fruit cage because they will exploit any opening. The fruit is just too tempting for them.
Thirdly annual pruning to keep the plants at optimal production. This is not as difficult as it is made out as long as you follow simple rules.
So with weed supressing membrane with mulch, adequate netting and annual pruning not very much work annually at all.