Files look fine but when I go to use them, the stoke and letters are different

I've been putting text in with a .25 stroke for years, now suddently the stroke lines seem much thicker and the text looks fine when in illustrator, but when I export as an svg as I've always done, the letter are super warped. They're different every single time I export, even if I make no edits and just export again. The white background one shows how it's fine, then the 2nd image shows how it warps.