For better visibility, Google has started testing bigger fonts in search results. This is good move from visitors’ point of view, but when it comes to SEO’s its another challenge to be accepted 🙂
Google Bigger Fonts and Search Results Without Google Ads:

With the increase in size of the font, only 3 natural listings are visible before the fold. Now, one must rank within the top 3 results for better Click Through Rate.
Google Bigger Fonts and Google Ads:

In case there are Google Ads for a search query only 3 Ads are being displayed before the fold. It will increase the competition among the bidders.
Google Bigger Fonts and Local Listings:

In case if it is a localized listing, the map and a related listing with structured data is showing up in the search results.
Google Bigger Fonts and Zero Click Searches:

When it comes to how to question, the resulted video listing has completely occupied the fold.