This comes up very regularly, and it is often forgotten that the old pension was earnings-related, so many people who paid full stamp and SERPS get significantly more than the New SP, which is capped. Widows who retired before 2016, I believe, get at least some of their husbands' pension (the SERPS part?), whereas those on the New SP don't get anything. Some people on the old pension get both SERPS and a widow's pension, which can take them well over the New SP rate.
Even without any widow's pension, the maximum additional (SERPS) pension is £222 a week on top of the maximum old pension of £176, bringing it to £398, which is obviously significantly more than the maximum New pension of £230 a week. I realise that not everyone qualifies for the top rate in either scheme, which complicates things further when it comes to fairness.
Comparisons between the two are not sensible. Anyone, even if they have not paid contributions, will be upgraded to Pension Credit, if their income is low enough. This is set at the level of the New SP, and can open the way to other benefits that can not be claimed by those who have paid full contributions to the new SP, so much of the discussion is academic anyway.
I agree that it is a mess, but as the pension is supposedly contribution-based it would be extremely difficult to sort it out in a way that is fair to everyone, particularly as many of those on the old pension have been getting it for many years longer than those on the new scheme.
Would people with SERPs enhancements and a widow's pension be willing to give those up so that payments are evened out? Would people who claimed the pension at 60 be happy to pay back the extra money, perhaps by deductions to their pensions? Probably not (and I don't blame them!) so how can that 6 or 7 years be credited to those on the New SP?
People on the New SP can't claim Pension Credit - should money be taken from those who do to equalise with New pensioners ? What about women who paid a full stamp for decades so that they would get a full pension in their own right? Should they just write that off and let those who didn't have the same rate as they do?
Changes to pensions, as with all benefits, affect people in different ways. Some benefit and others don't. I haven't done the sums as there is no point, but suspect I would be a lot better off if I had paid into SERPS, as I have paid NI since the age of 16 but was not able to pay into an occupational pension until the age of 37. I would certainly have more in the bank if I hadn't lived on savings for the six years when I would once have been claiming a pension. Is that fair? Maybe, maybe not. I chose to do that, just as others made choices about how much to pay in and how many years to work.
Losers would seem to be those who paid full stamp for the full number of contributions required for the old pension, but still get less than those who did the same under the new scheme, but even then, many will have retired and claimed at 60, so the loss is not a straightforward subtraction.
I would like to see all pensions increased, but I think that is very unlikely to happen when the benefits bill is so high across the board.