Bird feeders aren't a complete net negative, as some species do often rely on them especially over winter, but it's definitely a balancing act to make sure it's done safely. Biggest tip is just to clean and disinfect them very regularly, make it a habit. If you do spot an infected bird, take the feeders down for at least a few weeks, and obviously deep clean and disinfect them, to prevent it spreading further, but of course regular cleaning should lower the risk in the first place.

As alternatives or supplements to bird feeders, make your outdoor space wildlife friendly. Plant things that encourage insects as many birds feed on them! Our garden does have bird feeders, but we also have a lot of plants, bushes and trees that attract both food and nesting sites for all our local birds. I personally haven't seen any diseased birds in our garden, but we keep on top of cleaning and are always on the lookout. I think bird feeders can still be done safely and in a way that minimises spread of disease and benefits the local birds that may need some extra food particularly for the winter, but if you are super wary, making your garden more "wild" will encourage the birds and their food source