Conte is not a bottler like pochettino. He knew the league and he was the last one won the league other than pep and klopp all be it as chelsea manager though.
He will make spurs 80 + team coming season. Little help in luck here and there they can win it. I know it's not easy but not improbable.
He got a average team and yet finished above arsenal despite started his race lately. He always have the knack winning most against dross and that's much enough to challenge in my opinion if both liverpool and city slip up.
Conte is absolutely a top manager in league play and Spurs should be strong favorites for top four again. But they simply don't have the talent or depth to compete with City and Liverpool.
He actually had a ton of things in his favor last year: No European football after November. All important players other than Romero (Kane/Son/Dier/Hojbjerg/Kulu/Bentancur/Davies ) had nearly pristine injury records in league play. Six own goals scored by opponents over the whole season, no other PL team had more than 3. Six red cards also given to opponents, PL average was 2. Shit happens, it's football. But for all these reasons you can't just look at a small run of form and say that is the whole story.
More broadly, next season is just going to be an absolutely murderous grind. Depending on progression in the cups, Spurs and other clubs in Europe will probably play 55-60 matches, on top of many of the players having a World Cup right in the middle, with the 3-7 matches plus training and travel disruption that comes with it. Since they are in the CL and also are desperate to win a trophy, Spurs also won't have hardly any matches they feel they can truly blow off or deprioritize, beyond a favorable draw against a lower division side in the very early rounds of one of the domestic cups. More than any other year we've seen, next year will be a test of entire squads, which means that the talent of your best couple players becomes relatively less important than in a normal year (because they can't play every match, and Spurs won't have any competitions they are just blowing off like the ECL last year) and the talent of your second team more important than in a normal year. And even with a big summer Spurs will remain a top heavy side from a talent perspective. Their depth just isn't at the level of City, Liverpool, or even Chelsea.