Is ‘progressively worse’ the equivalent of ‘regressively better’?

An interesting question. I have not encountered "regressively better" other than in a physical science context (and that only a couple of times in many decades).

“progressively worse” = “regressively better”?

It may be useful to consider the four possible combinations of progress/regress and worse/better.

There are at least two connotations to progress/regress. The first is a simple sense of direction or time, as in advance/return.

These directions may be qualified, so that we progress towards worse things or towards better things. Similarly, with regress: we may regress to worse or better things.

From this perspective, "progress to better" and "regress to worse" describe movements in opposite directions along a scale in which what is ahead is better than what is behind. This is the normal optimistic view of progress/regress: the future will be better. It leads to the second and usual connotations of progress/regress, which are improvement/ deterioration.

Similarly, "progress to worse" and "regress to better" describe movements in opposite directions along a scale in which what is ahead is worse than what is behind. It is easy to think of contemporary political viewpoints of this sort.

But progress/regress (whether for better or worse) are not equivalent, for one describes advance, the other return. They are only equivalent in an associative sense, in that they both describe consistently the changes associated with movements either way along the scale.

It is interesting to think about “progressively worse” = “regressively worse”? If this were true, it would imply that things now are better than they were or will be: no matter how we move, things get worse, so we are at the best of all – an optimum.

Similarly, “progressively better” = “regressively better”? If true this would mean things get better no matter how we move, so we are now in the worst of all circumstances.