Contributors are using image trace and passing them off as vector files.

A majority of this contributors images are clearly made with image trace and being billed as, “Architectural Floor Plan Symbols and Furniture Icons Vector Set for Interior Design, Blueprint Drafting & Real Estate Marketing.”

https://stock.adobe.com/contributor/212180865/muhammad?load_type=author&prev_url=detail&asset_id=2018616994

This series in particular...

https://stock.adobe.com/search/images?filters%5Bcontent_type%3A3d%5D=1&filters%5Bcontent_type%3Aaudio%5D=0&filters%5Bcontent_type%3Aillustration%5D=1&filters%5Bcontent_type%3Aphoto%5D=1&filters%5Bcontent_type%3Atemplate%5D=1&filters%5Bcontent_type%3Avideo%5D=1&filters%5Bcontent_type%3Azip_vector%5D=1&filters%5Bfree_collection%5D=0&filters%5Binclude_stock_enterprise%5D=0&filters%5Bis_editorial%5D=0&filters%5Bgentech%5D=exclude&order=relevance&serie_id=2018616994