So far what I know is that transaction fees are not determined from Binance but from a network that is very full so transaction fees rise because they are busy,
No, AFAIK it's fixed. I remember the very first fees they charge is 0.0003 BTC but that was few years ago already, until it become 0.0005 BTC, and now it increases again.
Depends on a certain site, in stake they do have that fixed fee but it do changed up overtime basing up on the current price of Bitcoin but in most cases neither the network does have that
clear or having that traffic the fee would really be just the same. Basing into my own experience on which there are sites which does have that kind of dynamic kind of fees when it comes to withdrawal on which they would really be basing up with the current market condition and wont really be paying up came from their own pockets because we know that once that the network
would be congested then expect for those high fees and if ever that they would be having that free fee withdrawal then that would really still cost some expense on their side
so it would be just normal to have that dynamic.