In both singleplayer and multiplayer since the 1.14 update, the section sign has been inaccessible when using the book and quill for text formatting, including pasting it in. I've attached two screenshots that show the same text pasted into a book and quill1 comparing versions 1.13.2 and 1.14.4, though all versions since 1.14 have had this bug including the new 1.15 snapshot. Note in the 1.13.2 screenshot, it still showed the carriage return symbol which did exist in those versions, but has since been patched.

When I use /give to acquire the same book with the same text using json formatting, it appears fine. The command that works is listed below.2

Tl;dr: The Section Sign is inaccessible in-game in 1.14, meaning that formatting in Survival mode isn't possible. This includes the keyboard shortcut (Alt+ NUMPAD2 NUMPAD1) and pasting the character in,

–

¹ §lTe§1§lst§2§ling§3§o Te§4§ost§5§oin§6§og§0 §7§n1§0§n §8§n2§0§n §9§n3§0
§a§mHe§b§mll§c§mo§d Wo§erl§fd !§0
§kObfuscated§r
§0

² /give @p written_book{pages:["[\"\",

{\"text\":\"Te\",\"bold\":true}

,{\"text\":\"st\",\"bold\":true,\"color\":\"dark_blue\"},{\"text\":\"ing\",\"bold\":true,\"color\":\"dark_green\"},{\"text\":\" Te\",\"color\":\"dark_aqua\",\"italic\":true},{\"text\":\"st\",\"italic\":true,\"color\":\"dark_red\"},{\"text\":\"in\",\"italic\":true,\"color\":\"dark_purple\"},{\"text\":\"g\",\"italic\":true,\"color\":\"gold\"},{\"text\":\" \",\"color\":\"reset\"},{\"text\":\"1\",\"underlined\":true,\"color\":\"gray\"},{\"text\":\" \",\"color\":\"reset\",\"underlined\":true},{\"text\":\"2\",\"underlined\":true,\"color\":\"dark_gray\"},{\"text\":\" \",\"color\":\"reset\",\"underlined\":true},{\"text\":\"3\",\"underlined\":true,\"color\":\"blue\"},{\"text\":\"\\n\",\"color\":\"reset\"},{\"text\":\"He\",\"strikethrough\":true,\"color\":\"green\"},{\"text\":\"ll\",\"strikethrough\":true,\"color\":\"aqua\"},{\"text\":\"o\",\"strikethrough\":true,\"color\":\"red\"},{\"text\":\" Wo\",\"color\":\"light_purple\"},{\"text\":\"rl\",\"color\":\"yellow\"},{\"text\":\"d !\",\"color\":\"white\"},{\"text\":\"\\n\",\"color\":\"reset\"},{\"text\":\"Obfuscated\",\"obfuscated\":true},

{\"text\":\" n \",\"color\":\"reset\"}

]"],title:Book,author:"http://minecraft.tools/"}