No, it's not just cope.
There are two big cultural differences between Japan and the west at play here. This is stuff I got from talking to friends who lived in Japan, as well as a couple of native Japanese people, so it may be anecdotal but these people independently all said similar things. The standard caveat applies, too: those are generalizations, there are plenty of Japanese people who don't follow these cultural elements. Just not enough to change culture yet.
The first is that there's still a combination of conformist "I don't want to rock the boat" and "stiff upper lip" attitudes with a lot of people there. It's less prevalent in certain groups (particularly youths, or more westernized subcultures), but it's still a very powerful thing in general there. So a lot of nonviolent crimes and misdemeanors (particularly ones where someone is pressured to do something under pain of actual violence or some other form of retaliation) go fully unreported unless they're recurring, and even those may result in the repeat victim taking it upon themselves to
leave (either by moving out, or finding another job). While over here a neighbor playing loud music at 3AM may result in a police call, in Japan it's more likely that the person being bothered by it will decide to just grin and bear it.
The second is that the Japanese justice system is
weird. Justice in Japan is punitive, and they take pride in having extremely high conviction rates. To the tune of ~99% conviction rate, sometimes going so far as to force confessions out of innocent people. If they aren't
convinced they will bag the perp, they won't charge. They might not even officially
record the offense, as having large amounts of unprosecuted offenses in their area will make the local department look bad, and maintaining appearances is vital. They will definitely investigate serious crimes, but unless the media is breathing down their neck they won't make anything public until they have everything they need to secure that conviction.
These two elements put together mean that a lot of stuff that they consider unimportant simply goes unnoticed by the state and therefore also the official statistics. It's slowly changing (on the backs of a few serious sexual misbehavior cases being brought into the public eye), but the statistics for taboo crimes there are definitely not reliable and I would rather not try to make "gotcha!" points based on numbers that aren't accurate because it leaves you open to get "gotcha!"d back if better numbers come out.
Personally, from what I've learned talking to people (and admittedly no experience going to Japan), I think the actual numbers of sexual offenses in Japan are higher than officially presented, but still considerably lower than the western numbers in that image I was replying to. Japan is definitely no immigrant ghetto in Sweden (or
Rotherham for that matter...) but it's not the peaceful paradise of harmony weebs like to pretend it is. It's a place with serious social problems like everywhere else, otherwise their suicide rates wouldn't be so high. It just happens that their problems are different from ours so they're harder to understand at a glance.