That's true. Here in Scandinavia it's quite common. In fact, it was only yesterday an acquaintance shared with me they are being treated for a current infection. They were in good spirits though, and health.
While I am sure what you said is true, it really depends on the person. In our family we get a lot of ticks because we are outside a lot. A vaccine against Lyme disease I would get in a heartbeat. If your life is based on going from home to work, bar, restaurant, theater, movies etc. then this is really mostly irrelevant.
I don't know about how common it is, but my understanding is that tests for Lyme are fairly unreliable, leading to many people self-diagnosing themselves with Lyme, kind of like we're seeing now with 'long covid'.
The test detects antibodies. There's only so much to tell from that. What symptoms you'll have, when you'll have them, if you had it a long time ago, if you are infected but haven't produced the antibodies yet... these are things we can't tell just from the presence/absence of antibodies.
In The Netherlands ticks have become very invasive in the past few years, even in cities. I've gotten Lyme, and it certainly wasn't fun. I am happy this vaccine is on the way.
If you have basically any species of deer or elk plus anything green growing it's not that uncommon.
Your doctor friend might have been referring to "chronic Lyme" which is a very divisive issue. There are quack docs who will tell you you have it when you don't, there are docs who will angrily tell you there's no such thing, and then there are docs who wince a little a mutter about how there are things we don't know enough about.
