I used eye drops with preservatives when I only needed them to clear workshop dust from my eyes, several times a week. I now use drops several times a day and the preservative ones irritate and worsen my dry eyes. Heated eye masks and eyelid cleaning also help with dry eye, enhancing oil gland production, thereby decreasing evaporation rates. Here is a research paper on the topic: https://pubmed.ncbi.nlm.nih.gov/20302969/