But she said the long-term effects of the pandemic were likely to be minimal, and fees were expected to bounce back within the next two years.
A Strategic Pay survey showed there was an ongoing disparity in remuneration levels between the public and private sector; the 2021 findings highlighted a similar gap to that uncovered last year.
"With fees at small private-sector organisations often equivalent to those at some of our largest Crown-owned entities, it's a sad reflection of the value being placed on governance roles inside some of New Zealand's largest organisations," she said.
"Predictions are that this gap will only continue to grow over time, severely limiting the appeal of public sector board roles, and therefore the pool of talent available to serve in these positions," she said.
"I'd expect this to be a significant cause of concern for policy makers," Hendry said.
Hendry told the Herald there had been almost no movement in executive salaries over the period, particularly around variable payments.
"Covid has been a big deal and it's definitely reflecting in executive salaries," she said.
Many director pay cuts would have been voluntary, in line with requests for staff to reduce hours and accept lower pay.
"In many cases, executives and directors were probably working their hardest because the regular bi-monthly business meetings would not have been enough, particularly when Covid first hit," she said.
"Even the most experienced directors would not have been able to look back on another incident like this and use it as an example as to how to respond. It really has been a difficult and trying time."
Across the Tasman, Hendry said there had been a bigger push for directors to have more skin in the game on the form of share ownership.
"In New Zealand, you just don't see that same push to own shares or to have an equity component to director's fees," she said.
In its report, Strategic Pay said 47 per cent of respondents reported an increase in workload over the past 12 months.
This was initially fuelled by the need for a rapid response and adjustment to the uncertainty of the Covid-19 environment – and has been sustained by greater compliance-related issues, personal and professional risk and increased scrutiny and demand for transparency.
Further inroads had been to redress the gender imbalance on boards.
This year's findings showed 23 per cent of chairs and 37 per cent of directors are women – up from 20 per cent and 35 per cent respectively in 2020.
This is a substantial increase from almost a decade ago, where women made up only 12.5 per cent of chairs and 22.8 per cent of directors.
"It's encouraging to see us moving towards greater levels of gender balance, but the numbers are still so low," Hendry said.
"Diverse workplaces bring more efficiency, innovation and a wide range of perspectives and experience that businesses stand to benefit substantially from," she said.
Female board members are most prevalent in central government (52 per cent) and engineering (50 per cent).
Women were less likely to be included on boards found in the pharmaceuticals and mining/petroleum industries.
The median base annual fee paid to a non-executive chair in 2021 was $75,000, down from $80,000 in 2020.
Highest fees were paid to non-executive chairs within the mining/petroleum and manufacturing industries and lowest fees to chairs within the education industry.
Chairs of private sector publicly listed NZX companies are paid 62 per cent more (at the median) than those of unlisted private sector organisations.
The median base annual fee paid to non-executive directors in 2021 was $40,000, down from $41,000 in 2020.
