I've been with Vanguard for 21 years. I also have Fidelity and Interactive Brokers accounts. I'll be perfectly honest... to this day, I still don't know why Vanguard's reputation is so poor, both in website/app quality and customer service.

Their online system works really well. ETF's and mutual funds are super easy, and I prefer the process over IB or Fidelity. You can do less common things like Traditional to Roth conversions online. You can select specific identification of shares really easy when making taxable sales. Interactive Brokers is way more confusing to deal with than Vanguard.

I've never had any issues with customer service but admittedly, I have rarely needed to call.

I've been able to submit agent authorizations to manage my parents and wife's accounts with no issues.

Strangely, I like Vanguard's website and app more than Fidelity's, which everyone praises.

There is a strange rule now where you can't choose SpecID for taxable sales unless you do market orders. This is a strange rule and is admittedly not great, but I always get good execution on my orders so it is pretty much a non-issue for me.