For me, I love having ferns in my orchid pots, it gives a more naturalized look, also helps when deciding whether to water or not. And come on, orchids in cultivation should not have 'competition for nutrient issues' we nurture our orchids so well and provide nutrients in such excess, that if kept in check both the plants can live very peacefully without sabotaging each other.
My orchid pots have actually become a nursery for all my ferns especially my birds nest ferns and Blechnums.
In the first picture you see very young sporophytes of the birds nest fern growing with my Potinara love passion.
And in the next the huge mother plant.
This year I was able to plant out about 200 of these birds nest plantlets and about 15 Blechnums strating from just 7 and 2 mother plants respectively.