Sorry, but you're playing games with the numbers. The chart you show is not total number of SAR missions, it's the number that involve the Cpspas-Sarsat system. Basically the chart shows growth in the implementation of that system, not a growth of the overall number of SAR missions.
The RITA data
that MarkofSeaLife linked shows quite definitively that there has been a dramatic reduction of SAR missions
1985: 60,775 cases; 88,000 sorties
2010: 22,226 cases; 23,159 sorties
There are many other metrics on that site, and virtually every one shows a sustained and dramatic reduction of incidents over the past 25 years. The trend is unmistakable.
So while it may initially seem plausible that "false security" of electronics is leading to more accidents, it is not true. In fact, the statistics would seem to show the opposite - that the new technology is making people safer and helping them to avoid accidents. And when accidents happen, the likelihood of successful rescue goes up.
So maybe we should tone down the rhetoric a bit. Safety is getting better, not worse. Fewer incidents are happening. Fewer people are dying. Technology is a good thing.
I'll repeat my prior suggestion that TV shows, proliferation of camcorders and camera phones, and the instantaneous publicity of incidents by the blogosphers makes it SEEM like there are more incidents, but the data prove that there are actually fewer.