Hello Alberto,
The only thing more ridiculous than providing searchlights to allow the secondary armament to fight at night, would be to withhold training and practice so that the main armament could not join in. As apparently happened. For two decades.

What exactly is uniquely unusable on an Italian WWII fire control and weapon system when the sun drops below the horizon? Did they put padlocks on the turrets when it got dark?
Whether the French Navy was equally disorganised is utterly immaterial, but extremely unlikely.
It is also ridiculous, unreasonable and unconvincing to try and equate the inability to finance Hood's rebuild in the 20's and 30's in addition to that of all of the QE's (Warspite, Valiant and QE twice) and Renown, not to mention the carriers with this topdown decades-long institutional slackness exposed in the RN's opponent at Matapan. As you and Antonio are well aware, a plan for Hood's reconstruction existed, see ADM 229/20: DNC's Reports (1938-1939) on the Hood website, but as a fast, well armed and pretty well armoured unit she was perfectly suitable to go up against Bismarck at Denmark Straits. No lesser authority than Bill Jurens has given his opinion that Hood's protection was most unfortunate to be defeated.
Even to say that because your armour is inadequate, you should cower in harbour, bears no comparison with reality. Bismarck might only have shot at PoW. If Vittorio Veneto had been encountered at Matapan, Barham might not ever have been targetted.
You have said
As Tovey decided to use Hood, also Iachino decided to send back Zara and Fiume, knowing they were at risk as any other big Italian ship, but as in Tovey case , IMHO, Iachino cannot be fully blamed for having answered to a message received from Pola ("I require assistance and towing") as he had no other choice wanting to rescue Pola
There is no comparison. Iachino's decision making was "criminally" incompetent and muddled from the beginning. He had no idea where the enemy was, so he had no idea whether a "peacetime type" towing exercise was even feasible. Tovey knew Hood and PoW had a good chance of hurting or killing Bismarck and he needed two balanced forces with the ships he had.
Iachino knew his large cruisers were incapable of using their main armament even in defence and risking two more cruisers and their crews on a low chance of success salvage job in response to the helpless, pathetic bleating of Pola shows hopeless judgement. Cruel decisions must be taken. Sir John Cunningham in HMS Devonshire with 461 passengers onboard including the Norwegian King and government had to take a cruel decision to leave Glorious to her fate. That is bravery.
Cattaneo's original idea of sending a couple of expendable destroyers back to take off the crew and destroy the cripple at least made some sense. Instead he and his crews were pointlessly sent back into the mincing machine, with no offensive capability at all and no realistic chance of success in recovering Pola. Iachino wasted his men's lives.
Cattaneo's squadron formation almost guaranteed his destruction, and it is hard to believe that visibility was so variable that Cunningham's fire-control systems could track their targets when Cattaneo's lookouts could not even see 35,000 ton battleships. There is no comparison with Glorious' lack of vigilance believing they were leaving a war zone behind, with Cattano's wilful lack of preparation and vigilance
knowing he was entering one.
These pathetic attempts to equate British and Italian naval command decisions at Matapan and Denmark Straits are depressingly revealing.
All the best
wadinga