well remote working does make checking on the remote worker harder so more difficult to know what they are actually doing, but knowing if their tasks are difficult or similar things should be achievable just over chat.
I have noticed that people who review your code have no issue with remote work, and can easily assess your state of mind, personality traits without much more help like video and visits. It makes it harder for the people not reviewing your work.
Sadly you are right. In person, an unskilled manager can tell if it looks like you are working hard, even if they don't understand what you are doing. Remotely, they can't even tell that, and are effectively blind.