It's all about opinions, based on your relevant experience. The Lidl near you might not be as good (perhaps due to bad management) as my local one, but generally they tend to stock the same stuff. One thing that might explain the poor quality of the fresh produce you've had is that Lidl tend to use local suppliers, so perhaps the produce in your area, selected by Lidl, isn't as good? Dunno...
Don't like white sausage, so have no experience of that, but love Bratwurst (what they sell in market stalls in streets and in trains stations in Germany, fried with onions and served in buns with mustard), and trust me, the stuff in Lidl is as authentic as you'll get. You must've had it/seen it for sale when you've been over to the Munich hi-fi show. And the German beer sold in either Lidl or Aldi is genuine German Pils, and superb, especially the Octoberfest stuff and Lowenbrau they're currently selling!
As for the wine, you've either been very unfortunate or have bought the wrong stuff. Don't buy anything 'new world', or Spanish, as chances are it'll be crap. That's not Lidl's (or Aldi's) forte.
Stick with German wines or Italian or French, and you really can't go wrong, as long as you're spending £7 a bottle or more. Anything less than that is liable not to be a very rewarding experience. Their Prosecco (DOCG Valdobbiadene) is among the best I've tasted from any supermarket, and for that quality cheaper than found elsewhere. And their Chianti Riserva (Gallo Nero) is also excellent.
Also, their fresh pasta, particularly that of Aldi, is top-notch. These Girasoli, for example, served with your own homemade Ragu sauce [pic below taken from what I've eaten and subsequently posted on the food thread], are as good as you'll find in most UK Italian restaurants, and way better than anything I've had from Waitrose: https://www.aldi.co.uk/spinach-%26-r...75029129468700
Gorgeous! Oh, and the quality of their fresh Parmigiano Reggiano (DOC) is also better, IMO, than anything sold in Waitrose, or any other supermarket, for that matter.
Marco.