23:28:01.344: Output 'adv_stream': Number of dropped frames due to insufficient bandwidth/connection stalls: 27066 (51.0%)
I don't know why Twitch says you're streaming 1080p60, because you clearly aren't.
You're also dropping half your frames even at 2500Kbps, so you've either got a connection that is completely unsuited to streaming, or you have a network problem that needs addressing. Check your NIC, drivers, local cabling and router, then complain to your ISP.
Also from your logfile: 1) Update Windows, you're 2 years out of date, and 2) don't use multiple game/display captures in a single scene, it's a recipe for bad performance. Keep game and display captures separate, and either keep game captures apart in separate scenes or scene collections, or use a single game capture source and reconfigure it on a per-game basis. Multiple game captures can interfere even when inactive and make OBS less performant and/or less reliable.