what makes you possibly think that?
using a VPN is the equivalent of walking into a bank with a motorcycle helmet or a bataclava, don't be surprised of the unwarm welcome.
I've worked in bank and fintech around fraud. Blocked quite a few VPN/hosting at the network level so they couldn't even reach our network at all.
Why do you think so? Do you want your ISP to not know who you bank with? Do you not trust TLS? Is your network operator an active, advanced threat actor? What problems would you like to solve with VPN in this case?
They’re also known to use traffic shaping to websites they don’t like, and which they they should pay them more money to get to your eyeballs. Netflix and YouTube are popular examples here. When I can get much higher throughput to Netflix and YouTube when on VPN versus when I’m not using VPN, something is very wrong.
So, no. I don’t trust my ISP. Not at all. Not as far as I can bodily throw their HQ building.
They also fuck with your VPN connections. Which is why I have accounts with multiple VPN providers.
Ads can be changed with plain HTTP requests, or DPI can be used to gain info about the HTTPS request and possibly block subsequent requests. The I in DPI is for inspection, AFAIK modification would be very difficult.
I've been doing this with RamNode for a few years with their $15/year OpenVZ mostly via SOCKS with DNS passthrough (the main disadvantage of this is that it doesn't allow direct DNS resolution and some adblock techniques require being able to do that). This includes a fixed dedicated IP address. Presumably they will eventually support wireguard and then everything should work without fuss (you could setup OpenVPN if you are so inclined and I think would need to if you want to additionally use anonymity providing VPNs on top of that). There are still a few issues with various sites but it sounds like it is quite a bit less annoying than anonymous VPNs, at least once Google and Cloudflare figure out what you are doing. The 500GB bandwidth is per month and generously accounted so I've only once reached it (it would be $4/month for an additional TB). I'd guess there are a number of low priced ISPs that would work. Most software I've used seems to respect ALL_PROXY=socks5h://... these days although not all.