If you’re applying to work in development or production and have a production company on the side that produces web series, it’s probably worth including on your resume, since it supports your ultimate career goals. Same goes if you’re a script reader looking for development jobs. But what about skills and experience that aren't so industry specific? Maybe you are a talented coder or graphic designer, so you build websites. These are useful skills, especially at digital companies or for marketing positions, but if you're looking for work in development, production, or representation, including them in your timeline may distract employers from other recognizable companies you’ve worked for or cause your more pertinent skills to get lost. Unless you need to fill space or believe these experiences are key selling points, you should move the these extra endeavors down into the skills or interests section of your resume.
If your side hustle is totally unrelated to the industry -- Uber driver, Nordstrom salesperson, nanny -- leave it off. The only exceptions are if you’re a recent college grad without much professional or extracurricular experience or if you need to fill gaps in your resume timeline. In these cases, you can include the position, but make sure you highlight transferable skills, like customer service.