The problem with comparing COVID to the flu or RSV is that the latter pair of illnesses can't lead to long forms, as is the case with Long COVID. The five-day isolation rule was and still should be used to ensure that those who have contracted the illness — whether asymptomatic or not — don't give it to someone else who could then develop long-term issues.
Isolating over minor symptoms was something we did early during COVID — but the pandemic is now over and it's time to move on. One of the most serious issues related to this is the skyrocketing rates of chronic absenteeism across America's schools. Despite most governments having dropped old COVID rules, record numbers of students are still using the memory of the pandemic as an excuse to skip class and stop learning.