Samsung has actually increased the bezels in the note 9
The Galaxy Note 9 is the best phone Samsung has made. It’s arguably the best phone yet period. It designs and features are very thoughtfully made to offer improvements over its predecessor, the note 8. Like the placement of the fingerprint sensor, the new S-Pen. A phone which offers a closer experience to the note 9 is the Samsung Galaxy s 9+ from which Samsung made improvements to get the note 9
Samsung has further pushed out the top and bottom bezels of the Galaxy Note 9. But what you might not have noticed is that they widened or increased the side bezels of the note 9. This results in a slightly lower screen to body ratio from 84.2% in the S9+ to 83.4% for the note 9 which is a somewhat a risky move seeing how far other companies are going to bring up those number like the OPPO which has gone as far as putting motorized cameras in phones like the OPPO Find X which has a screen to body ratio of 87.0%
This was done in a bid to improve the usability of the Note 9. One has a higher tendency of involuntary screen touches especially when reaching across the screen on The S9+ which has this flaw. From a usability standpoint, it renders a noticeable improvement over the S9+ especially when reaching across the screen. This somewhat counter-intuitive design change reduces the chances of involuntary touches when reaching across the screen which makes it more usable than the S9+. So thinner bezels are not always the answer for Samsung, especially with their curved design displays.