If you want more controversial things about squash, here are two that I posted here last week:

1. "How squash merge can break Git repos with submodules", about a situation where squash merges silently broke a repository: https://news.ycombinator.com/item?id=40846596

2. "Git: please stop squash merging!" giving some technical explanation about what squash merges actually are under the hood and how the misconceptions about Git leads to invalid "pros" about squash merging: https://news.ycombinator.com/item?id=40840572