Valneva and Pfizer announce Phase 2 study for Lyme disease vaccine candidate

As someone who had Lyme twice.... YES PLEASE.

Can anyone give some insight as to why a vaccine hasn't been possible using more traditional technology?

It's nothing compared to the other tick disease: tick borne encephalitis. Thankfully there's a vaccine against that

There was one but it was taken off the market. It's a bit of a sad story because it worked but because of unfounded claims that it had side effects, it lost trust of the public:

"In clinical trials involving more than 10,000 people, the vaccine, called LYMErix, was found to confer protective immunity to Borrelia in 76% of adults and 100% of children with only mild or moderate and transient adverse effects. [...] Subsequently, hundreds of vaccine recipients reported they had developed autoimmune and other side effects. Supported by some advocacy groups, a number of class-action lawsuits were filed against GlaxoSmithKline, alleging the vaccine had caused these health problems. These claims were investigated by the FDA and the Centers for Disease Control, which found no connection between the vaccine and the autoimmune complaints.

Despite the lack of evidence that the complaints were caused by the vaccine, sales plummeted and LYMErix was withdrawn from the U.S. market by GlaxoSmithKline in February 2002, in the setting of negative media coverage and fears of vaccine side effects.",

https://en.wikipedia.org/wiki/Lyme_disease#Vaccination

Lets hope so, then we can prevent instead of treat :)