So, four facts and an opinion.
The major poultry ops expect deaths in shipping. USPS costs them millions of birds each year. Nothing to do with the hatcheries, everything to do with USPS. But since USPS is the ONLY option, they don't complain loudly. They don't even file claims for the losses. Its now part of their operational expenses. Without regard to the hatchery (Hoover, Meyers, Ideal, Cackle, etc) in question.
The Pandemic has made USPS losses worse, for a host of logistical reasons. Freak weather doesn't help either - the current heat wave in the south, or the late hard freeeze last year.
As
@iwltfum correctly observed above, stresses in ealry childhood have lifelong consequences. Something I have to repeatedly mention on feed threads, after the damage has been done.
TSC has a (well deserved, in my rarely humble opinion) reputation for misidentified birds because they don't train their employees, not because Hoover routinely misidentifies birds. If you hget an invoice that says 40 white leghorn, 40 Cx and have 80 birds in two boxes (or a box with a divider), chances are you got what you ordered. When TSC employees take that box and invoice, but don't know A from B, then place them in stock tanks in the back, where they may (or may not) be seperated before moving them to the sales floor, and later take returns from the sales counter of people who changed their minds before buying... Mistakes happen, frequently.
Finally, and anecdotally, I have not been pleased with the quality of any bird I got from Hoover (my entire initial flock, by way of TSC). They are adequate, hatchery quality birds, in no way exceptional. For their price and availability, they get the job done. If I had more specific needs, or a higher bar against which I measured "success", they would not be my first choice.