Neither are anywhere near a "lock", or even a strong candidate.
I understand they are the league's best TEs, but they've been playing for 7 and 5 years, respectively. Are they on their way to becoming HOF TEs? Yes. But if their careers ended tomorrow, neither would be even close to locks.
Shannon Sharpe played 14 seasons and has significantly better stats then either of them, and isn't in. Hell, Sterling Sharpe played 7 seasons and had better stats than both, and isn't in.
I really think people overrate current players and their perception compared to all time players and HOF worthiness.