I have been in this business for twenty years and I am growing tired of the dance. Back when we ran actual bare metal out of actual closets, you shook a man's hand and you trusted the route. Now kids these days want a looking glass, a speedtest, a traceroute, and probably your grandmother's maiden name before they will part with five dollars.
I asked OVHcloud for a test IP last Tuesday. Sales went dark. No reply. I followed up. Nothing. Mark my words, this is a provider that has something to hide—oversold transit, congested peering, or worse. The ones who refuse are the ones who should worry.
Yet I see the other side. The tire-kickers who burn ten hours of support time and buy nothing. The "testers" who are really competitors mapping your network. I get it.
Still. A test IP is due diligence. Any shop worth its salt lists them unprompted. The rest deserve what they get when the complaints start.