Slow Bulk Smush

Good evening,

this morning I started a bulk smush, I had a bit more than 4200 images in my website (https://frnshx.com/). Now, after the whole day, the bulk smush smushed only 223 images. Is it normal? I mean, it looked me a bit too slow.
So I canceled the bulk smush and retried different times again, but after hours it smushed only 5-10 images. What should I do ?

Here’s a screen:

https://pho.to/AkXpV

Thanks in advance,
Giuseppe