Certain phases of work and types of teams do alright remotely - typically a team with a lot of senior engineers in mid-project flow with few external dependencies. But a team with a significant number of juniors, faced with multiple blockers or external dependencies will underperform badly compared to in-person working.
Whole days will go missing because of a lack of effective communication - the simple ability to lean over and check or ask how someone is doing. Not to mention the inability of learners to just pick up information through incidental conversation and overhearing other people talking.