Practically all British manufacturers were known for electrical flaws in the 70's, and 60's for that matter. I was a mechanic in the 70's and remember a women bringing in her Spitfire that she couldn't drive at night because when she switched on her lights, the ignition cut out. That's how jokes like "Why do the Brits drink warm beer? Because Lucas manufacturers their refrigerators!" came about

. Lucas the prince of darkness!

It wasn't just Jaguar back then. Since Ford bought Jaguar, that hasn't been an issue and under Tata and now Tata/Chery, much the same.
The electrical issues now are the issues that plague Audi and Volkswagen and Mercedes and Fiat and Volvo and Ford and pretty much all modern manufacturers; Technology. You see very few people not being able to drive their cars due to electrical faults, but you see many that have problems with their dual zone electronic climate control systems and the whiz bang 88 speaker 5KW entertainment systems.
So what I'm saying is these electrical faults are much different than the ones suffered by British manufacturers in 60's and 70's and are common to most manufacturers today. Much like comparing apples to chainsaws. Don't get me wrong, I'm not defending Jaguar. I think they are junk when talking about long term reliability. That's why I leased for three years as opposed to buying. Even Jaguar should hold together for the length of the warranty! Hope you enjoy yours. Keep the shiny side up and the greasy side down.