I don't think he's not really "not being backed" necessarily. What Conte's system that he refuses to deviate from requires is elite attacking wingbacks. I don't believe we're willfully not buying any, I think they're very few and hard to come by and he's done a poor job of coaching up/integrating what we have in the mean time.
Levy 100% needs to pay Porro's release clause and be done with it, though. >£40M isn't even that much for a player you intend to be a plug and play starter in the top 6 of the PL these days. In all reality, I feel like he's turning us down because the need is glaring, it's doubtful Conte doesn't want him, and, again, it isn't much money comparatively.
We have a single wing back with any quality and he's contributed to 8 goals since being here ... there's not a coach alive who will train Emerson, Doherty or Sessegnon to be anything other than extremely mediore footballers.
Even Doherty, a highly limited mid-table level player with 1 or 2 standout attributes, has contributed a reasonable amount of g/a. There's nothing more Conte can do with these players, you could have Pep or Klopp here and it would be the exact same situation,