I think it’s both a good and bad thing if the number of annulments have been increasing. It’s good because somebody applying for an annulment in the Catholic Church is usually an indicator that they are converting or reverting to Catholicism, or at the very least, they care enough about the Church’s teaching to actually marry according to the Church’s laws.
It’s also bad because it means an increasing number of invalid marriages are taking place, both amongst Catholics and non-Catholics. This wouldn’t be as common if more people had a better understanding of the meaning of marriage and its corresponding responsibilities, so this could be a sign that we Catholics aren’t doing a good enough job catechizing or evangelizing others about Jesus’ teachings on marriage.
I once read somewhere that Catholics in the USA make up only 6% of the global Catholic population, yet account for around 41% of the Catholic annulments granted in the world. A Catholic priest and a Catholic canon lawyer have made a couple of interesting observations in response to this. The priest pointed out that the USA is a developed country with advanced infrastructure, modern technology, high rates of education and literacy, reliable transportation, etc. In comparison, many of the poorest of the poor in impoverished nations either might not have the opportunity to apply for an annulment (some who live in very remote regions may not even have access to a priest for weeks) or take years to complete the paperwork and other parts of the process. In the USA, it usually takes around a year, more or less, to complete the process.
Additionally, the canon lawyer mentioned that Catholics are a minority in the USA. It is understandable there would be more annulments granted in the USA than many countries with pre-dominant Catholic populations because there are more conversions to Catholicism (there are fewer people to convert if nearly everyone is already Catholic in a predominant Catholic country) and more opportunities for Catholics to marry non-Catholics outside the Church (decrees of nullity due to lack of canonical form).
In other words, things can be more complicated than they seem.