I suppose I shouldn't be so negative... Telles may turn out to be a fine left back. Maybe he'll be selected for the PL team of the season, which would be fantastic.
The 30,000 foot view is that this transfer period, in my opinion, has been pretty poor. We had real momentum at the close of last season. I know this is a pandemic, etc, etc, but better leadership of the club would take that as an opportunity to bring in truly world class players. Other clubs saw this as an opportunity (Chelsea, City, Everton, Spurs).
In a vacuum, I support this transfer. But the failure to, as most of you have mentioned, sell our deadwood to reduce our wage bill, fill our needs (RW, CB, DM are top priorities in my opinion), and construct a squad with a chance to challenge for the league and trophies is worrisome.
It's hard to get excited for a LB signing that probably won't move the needle. Does Telles' contribution bring us into top 4 contention? I doubt it. It's more of a treading water type of move, and given Shaw's injury history, probably needed. If I had to guess, maybe a Gabriel Heinze type of addition? Solid, but isn't going to win you trophies, especially when you have so many other holes throughout the pitch.