CDC lists incidents of Lyme disease in terms of population, meaning you can see what percentage of people get Lyme disease, rather than just how many people get it. Helpful because as population increases, naturally the total number of sick people also increases. What I see when I look at the chart is that the percentage of people affected does not seem to be changing.
It's a nasty disease, especially when left untreated. And you can lower your risk with smart clothing choices, bug repellent, and prompt tick removal. So by all means do those things.
But I'm not seeing any data to support the idea that more people are becoming affected for any reason other than the fact that there are more people to bite.