Pope JPII canonized 482 new saints, Pope Benedict 45 saints, and Pope Francis has canonized 838 new saints. While many of them were from past centuries, there are a lot more saints of the 20th century than the handful you mention. Using Wikipedia as a source, which is likely an incomplete list, and limiting myself to saints who died after 1910 so they lived at least 10 years in the 20th century, I came up with at least 75 canonized saints of the 20th century already, and that’s not counting the large number of beati.
Saints usually take at least a century or more to officially canonize so it is highly likely that future eras (assuming the world doesn’t end first) will see many more saints canonized from our centuries (20th and 21st). There are a good many venerables and beati already in the pipeline.
Furthermore, the number of official canonizations, which are usually related to the Church wishing to emphasize certain examples of saintly people and also to the groups who have resources and motivations to push a canonization cause through, hardly reflects the number of people whose lives are saintly and who go to Heaven. It is highly likely that there are future saints walking among us today who will never be officially recognized by the Church on earth, and saints who recently walked among us, who will never be officially recognized by the Church on earth. We simply don’t know what’s in each person’s heart, nor could we possibly know, nor do we need to know.
Like I said, human nature doesn’t change.
If it makes you feel better to think that this era is somehow less holy than the past, feel free; I personally see pretty much all ages as equally holy and equally evil, in different ways. In any event, some saint from centuries past going without sleep is hardly a bellwether for us today when going without sleep could cause somebody to have a 10 car freeway pileup killing innocent families. And as for what penance people do today, the ones doing the most penance likely aren’t going to tell you or advertise to anyone that they’re doing it.