Email Client: ???
Terminal: ???
IDE: ???
File manager: ???
Basic Text Editor: ???
IRC/Messaging Client: ???
PDF Reader: ???
Office Suite: ???
Calendar: ???
Video Player: ???
Music Player: ???
Photo Viewer: ???
Screen recording: ???
Web Browser: Firefox
Terminal: LXTerminal
IDE: LXTerminal
File manager: PCManFM
Basic Text Editor: Vim
PDF Reader: Xournal - http://xournal.sourceforge.net/ (useful for annotating PDFs also)
Office Suite: LibreOffice
Video Player: VLC Player
Music Player: cmus - https://cmus.github.io/
Photo Viewer: Image Viewer
Screen recording: Simple Screen Recorder - https://www.maartenbaert.be/simplescreenrecorder/
Email Client: ProtonMail in Firefox?
Terminal: Gnome terminal
IDE: vim
File manager: my shell
Basic Text Editor: vim
IRC/Messaging Client: web; used to use irssi, but I don't do IRC as much anymore, so it's mostly freenode's web client now
PDF Reader: Firefox
Office Suite: I don't bother, but I suppose LibreOffice occasionally
Calendar: the one built into GNOME
Video Player: Firefox, VLC
Music Player: I don't bother
Photo Viewer: the one built into GNOME
Screen recording: idk, I do it so rarely that I just pick one up when I need one
Honestly, must of my Linux time is spent in the shell, browsing the web, or playing games on Steam, mostly in that order. I used to be picky about my software (used to use XMonad with a curated set of keyboard-driven software), but GNOME seems to work mostly okay these days without fuss, so I've been using it.
I guess I'm trying out KDE because I'm moving to opensuse, so replace some of the stuff above with "whatever comes with KDE". I really don't care that much anymore until something doesn't work right, and that's pretty rare anymore.
Terminal: Terminal (with oh-my-zsh)
IDE: VS Code
Basic Text Editor: VS Code
PDF Reader: Brave (Chromium)
Office Suite: Google Docs/Sheets etc
Calendar: Google Calendar
Video Player: VLC
Music Player: mplayer
Image manipulation: GIMP
The main things I always add are GIMP, Brave, oh-my-zsh and VLC. Getting a good/working browser does most work for me.
Email Client: mu4e (mbsync for IMAP, msmtp for SMTP)
Terminal: Gnome Terminal in DE or Alacritty in WM
IDE: Emacs
File manager: Emacs dired
Basic Text Editor: Emacs
IRC/Messaging Client: Weechat
PDF Reader: Zathura
Office Suite: LibreOffice or Google Docs
Calendar: Emacs org-agenda (mostly iPhone calendar though).
Video Player: mpv
Music Player: Spotify
Photo Viewer: eog
Screen recording: n/a
Email Client: mu4e on emacs
Terminal: urxvt
IDE: vim and shell
File manager: shell
Basic Text Editor: vim
IRC/Messaging Client: weechat
PDF Reader: evince though I rarely use it
Office Suite: libreoffice though I rarely use it
Calendar: org-mode on emacs
Video Player: mpv
Music Player: mpv
Photo Viewer: viewnior
Screen recording: simplescreenrecorder though I rarely use it
Email Client: Delta Chat
Terminal: Terminology
IDE: Geany
File manager: PCManFM or Rox-Filer
Basic Text Editor: Leafpad
IRC/Messaging Client: Riot.im
PDF Reader: Okular/Evince
Office Suite: LibreOffice
Calendar: California
Video Player: SMPlayer
Music Player: DeaDBeeF
Photo Viewer: nomacs
Screen recording: peek
Email Client: Evolution
Terminal: Terminator
IDE: Vim or Geany
Basic Text Editor: Vim or Geany
Office Suite: LibreOffice
Video Player: VLC or SMPlayer
Music Player: Quod Libet
Screen recording: Kazam or OBS