NFL should have put a stop to this crap the first time it started last year.
There is absolutely no “right” to utilize one’s employment, uniform, etc. to conduct personal political protests.
You want to protest? Do it on your own time, your own dime.
For one thing, the NFL is a brand. The 49ers is a brand. These actions disparage the brand and make it less marketable, and ultimately hurt the bottom line.
Imagine Skippy Peanut Butter or Cracker Jacks or any other famous brand putting up with one of its team hurting the brand's image. The offender would be gone in one quick jiffy.
Roger Goodell would certainly give Mitch McConnell a run for his money in a spine-bending contest.