It's a lot easier for me to observe a junior struggling, spinning their wheels, and give corrective feedback in the office. I don't know the remote equivalent of glancing at their screen and body language while I get up for a bathroom break.
Listen to what they say during the daily team meeting, and occasionally ask by chat how they're doing. It's true that it has to be a bit more explicit, and it may be a bit slower, but it's far from impossible.
That's one point of contact per day. I was able to continuously be aware of anyone struggling before. I can't continuously ping them throughout the day. Even 4 times a day seems much too high contact to not be patronizing, and that still leaves them to stew for up to two hours at a time
It's really this simple. Junior employees need to be more actively managed than senior employees. They literally do not know what they're doing, that's what makes them junior. Remote or local, they need more oversight to help them learn and become productive.