There are no reliable statistics about frum divorce rates from the past or the present, so we don’t know whether they are going up or down. Aren’t people just making guesses based on their experience?
Goyish marriage rates increased dramatically for a few decades, perhaps because of feminism and the end of no-fault divorce, and then have slightly decreased (possibly because an increasingly small number of non-Jews gets married anymore aside from the educated upper-middle class). But their divorce rates are probably still far higher than ours.