John Mueller of Google clarifies that Google does not penalize those websites that are using old HTML and Table. According to Google, it will not impact users Google’s rankings.
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Google says most of the times’ web is either broken or invalid but in that condition, Google needs to find out a way of crawling, indexing, rendering and ranking it. Invalid HTML does not affect users in terms of Google ranking. Therefore website owners should not worry about that perspective.
Further, Google added, broken things on the website will give an immensely negative impact on the site users. Negative impact on-site users may lead to less traffic. Google does not even count this as a broken schema or markup.
Tweet By John Mueller:
1 – no, we don't penalize sites that use old-school (or invalid, table-designs, etc) HTML. 2 – I'm not sure what you mean with "boilerplater sites".
— ? John ? (@JohnMu) November 18, 2019