This is all personal preference. My preference is to have a filter on the front of my lens for protection. I do take it off for certain shots. But I walk through too much brush, crawl around too many rocks and have too many nieces and nephews that like to grab my camera for me to not have a filter. I tend to go with all three levels of protection: lens filter, lens hood and lens cap. It blows my mind, but I know photographers that don't do any of the three and apparently their gear holds up just fine. Just one of those things, you could go through your entire life and never need a seatbelt. I still wear mine.
Roger did make note that the issue was with cheap/bad filters and not with good filters. In fact, based on the second paragraph of the link, I've always assumed that Lensrentals sends their lenses out with good filters installed. While there is an impact to stacking 5 good filters, no one does that. While this is a bit dated at this point, lenstip.com reviewed a number of UV filters and provides photos with and without a single filter.
Also, how valuable a lens has to be to justify a filter is also personal preference, but a few that I'd buy a filter for that do not come with hoods include the EFS 17-55, EFS 15-85, and EFS 10-22. At one point I owned the EFS 15-85 and EFS 10-22. I bought both lens hoods and filters for both.