Index: wp-content/themes/twentyseventeen/assets/css/editor-blocks.css
===================================================================
--- wp-content/themes/twentyseventeen/assets/css/editor-blocks.css	(revision 58682)
+++ wp-content/themes/twentyseventeen/assets/css/editor-blocks.css	(working copy)
@@ -508,7 +508,9 @@
 }
 
 /* Quote */
-
+:root :where(.wp-block-quote[style*="font-weight"] *[style*="font-weight"]) ~ cite {
+	font-weight: inherit;
+}
 .wp-block-quote {
 	color: #666;
 	font-size: 18px;
Index: wp-content/themes/twentyseventeen/style.css
===================================================================
--- wp-content/themes/twentyseventeen/style.css	(revision 58682)
+++ wp-content/themes/twentyseventeen/style.css	(working copy)
@@ -522,6 +522,10 @@
 	margin-top: 0.5em;
 }
 
+:root :where(.wp-block-quote[style*="font-style"] *[style*="font-style"]) ~ cite {
+	font-style: inherit;
+}
+
 address {
 	margin: 0 0 1.5em;
 }