doc: revise assert legacy mode text

Revise the text for the `assert` module's legacy mode to make it simpler
and more scannable.

PR-URL: #28315
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: Trivikram Kamat <trivikr.dev@gmail.com>

Author: Trott

doc/api/assert.md

@@ -121,18 +121,21 @@ Please note that this will also deactivate the colors in the REPL.
 
 > Stability: 0 - Deprecated: Use strict mode instead.
 
-When accessing `assert` directly instead of using the `strict` property, the
-[Abstract Equality Comparison][] will be used for any function without "strict"
-in its name, such as [`assert.deepEqual()`][].
+Legacy mode uses the [Abstract Equality Comparison][] in:
 
-It can be accessed using:
+* [`assert.deepEqual()`][]
+* [`assert.equal()`][]
+* [`assert.notDeepEqual()`][]
+* [`assert.notEqual()`][]
+
+To use legacy mode:
 
 ```js
 const assert = require('assert');
 ```
 
-It is recommended to use the [`strict` mode][] instead as the
-[Abstract Equality Comparison][] can often have surprising results. This is
+Whenever possible, use the [`strict` mode][] instead. Otherwise, the
+[Abstract Equality Comparison][] may cause surprising results. This is
 especially true for [`assert.deepEqual()`][], where the comparison rules are
 lax: