Unity VS HTML5 - when is it okay to use canvas?

Question

JavaScript

Good time. I want to understand for which genres of 2D games html5 is well suited and in which it will definitely sag. I specialize in JS, for rendering I'm looking at React + Canvas. I need to imagine in what cases I can apply JS skills without losing quality and which areas of games are better to refuse.
I will explain the question in order to warn the holivar. I now need to understand not which of them is better (I suspect that Unity is out of competition), but in which cases it is normal to use html5 canvas. Although, for example, for visual novels, I doubt Unity's leadership - it seems to me that it is more convenient and even more efficient to do this on canvas. In games like Match3, I see no difference in speed or convenience, although in some cases you have to pay for Unity.
I hope you will help to form a complete picture of the difference between these technologies. Thank you.

Answer 1

for rendering, I look at React + Canvas

When you do something on Canvas, there is no point in React, and in game dev it will only get in the way.
Pure 2d context in JS is obviously a bad idea all the time, honestly.
Get off your goals. If you only target the Web - take Pixie and make great fast games.
If you want more platforms - definitely take Unity.