NYT: Chinese and Russian spies routinely eavesdrop on Trump’s iPhone calls (arstechnica.com)

I think it's important to note that this is only known to happen when he uses his personal iPhone. He has a separate, secure line that he also uses.

For that reason, I don't see evidence in this story itself that breaches are becoming more frequent. Previous presidents also had secure lines, presumably because consumer-grade communications have never been secure enough for a president.