Well, I took the trouble of reading
the English summary of the 2021 report by France's Pension Advisory Council (COR). Two things to consider:
1) The report makes it clear French pensions are already not being funded just by social security contributions - the "contract" has already been broken for a while now:
2021 COR Report wrote:How is this expenditure financed?
Levies to finance pensions currently represent almost 31% of working people's income. 75% of the financing of the pension system comes from social contributions. The rest of the resources are made up of earmarked taxes and other resources which come from State subsidies and transfers from third-party organisations, such as the unemployment insurance or the family branch of Social security.
Those "earmarked taxes" are tantamount to a hidden increase in the "agreed" contribution rate.
2) The projections already acknowledge that pensioners will see their relative living standards - compared to the average worker - decrease from the current high levels. That's why the system is "sustainable", essentially by not pampering retirees as much as they are now.
2021 COR Report wrote:Why would the share of pension expenditure fall in GDP in the long run?
The share of pension expenditure would fall in the long run despite the ageing of the French population; the ratio between the number of people aged 20 to 59 and those aged 60 and over would drop from 1.9 in 2020 to 1.3 in 2070. The impact of this demographic ageing on the pension system would be slowed down by the increase in the retirement age, which would rise from 62.2 years in 2019 to just under 64 years around 2040 with unchanged legislation, under the effect of past reforms and the increase in the age of entry into working life. This increase since 2010 has been accompanied by an increase in the employment rate of older people. The ratio between the number of contributors and the number of pensioners would nevertheless decrease, from 1.7 in 2019 to 1.3 in 2070.
However, despite this unfavourable demographic trend, pension expenditure as a percentage of GDP would decrease due to the fall in the average pension relative to earned income: pension would continue to grow in constant euros, but less quickly than income. Thus, the gross pension relative to gross income would vary between 31.6% and 36.5% in 2070, compared to 50.1% today. The stronger the growth, the sharper the decline in this ratio.
It seems unlikely pensioners, who will represent a larger share of voters, will accept to see their living standards worsen (increase less) relative to that of younger voters.
The European Commission's 2021 Ageing Report paints a worse picture of the French pension system, expecting for social security contributions to be able to cover pension spending on their own only in 2070 and for public spending on pensions as a percentage of GDP to be higher than the COR's forecast until around 2060. This is because the 2021 Ageing Report assumes fertility, long term increases in productivity and life expectancy will be lower than the COR's 2021 Report.