I made an account to comment on this.
I work for T-Mobile at one of the call centers, so I take calls all day about HSI. However, I'm NOT acting as a T-Mobile rep with this post.
I'm not sure where anyone said we don't prioritize data speeds, we do. It's right on the website we prioritize during high stress periods.
Also, when I look at the signal strength in our systems, it'll tell me if they're working on the towers and sometimes it'll give time expectations and sometimes it won't. The tower engineer teams sometimes don't have an ETA if it's day 1 of an issue.
Modernization is sometime they do all the time, it's pre-scheduled out but 90% of customers don't notice the effects. They don't send texts because it doesn't typically cause massive issues.
Also, we aren't allowed to talk to customers about de-prioritization, there's a big old red label that pops up in system to warn us against it. Having said that, I'll tell customers sometimes anyway because I don't like avoiding the truth. I usually try to get them an upgrade to Magenta Max so they can avoid prioritization altogether, if I think it's right for them.
Now, I don't really recommend the HSI to anyone unless their signal strength with their phones is great at home because while they use different bandwidths, it's still a good indicator for expected service levels.
Now having said all that, I think once they get all the towers upgraded for HSI and they start getting a better idea about local levels of demand, I feel like they'll take away the prioritization with a HSI deluxe service like MAX.
Again, I'm off the clock with this post, I'm not being paid to post this. (It'd look a lot different if I was.)
Also, I use Xfinity and I get regular non-schduled service interruptions all the time. Lasts 6 -8 hours sometimes and I'm paying $150 for no cap, no prioritized 600MBPS. So... just saying lol.