"The onus is on all of us" vs. "The obligation is on all of us"

[GoodTaste]

A 2020 global Gallup survey found that 92% of respondents viewed mental health as being equally as important to overall wellbeing as physical health, but people were not confident about how best to address mental ill health. Most thought talking to friends and family was key, but that option relies on low stigma and discrimination. The onus is on all of us to act in our personal and professional lives to improve the mental health of ourselves, loved ones, friends, and colleagues. Ending mental-health-related stigma is a goal that must be pursued.

Source: The Lancet

Can we end stigma and discrimination in mental health?

“I can't open up about it at work since companies still have the perception that people with mental illness are unstable and unable to function normally”

www.thelancet.com

What is the difference between "The onus is on all of us" and "The obligation is on all of us"？ Do both share the same meaning yet the former sounds a bit old-fashioned since the word onus is Latin?

 

[emsr2d2]

The original is completely natural and native speakers would all understand it. It doesn't sound at all old-fashioned. If I absolutely had to change it, I wouldn't replace it with "obligation". I'd use "responsibility".

"The onus is on [person/pronoun/company] ..." is used extensively in BrE.

 

[SoothingDave]

"The onus is on us" is a bit of word play.