Modric is 35, Ramos is 34. They are the best in their position, but their time is running out.
They are the best in Real Madrid at their positions but in La Liga they are not. They are certainly not the best in Europe, if you compare them to top players at their positions.
And we need to prepare a replacement for them. But it is not. And it will not be in the next couple of years. Since Real has no money. The failed transfer policy of recent years. brought Real to this state.
Real Madrid has lot of fund for transfer but the problems for them, in many decades is their club's financial budget is based on debt. They have many loans and the pandemic Covid-19 put not only Real Madrid but also many clubs under financial bailouts. They sure don't have big fund for transfer now and in near future.
Real sold Hakimi to Inter, although he could easily replace Carvajal now. Sold Llorente to Atlético Madrid, although he could easily replace Modric or Cross. Regilon really played worse than Mendy? But he was also sold. These players could safely play at the base of Real Madrid and no worse than the current players. How much money essentially wasted.
Those transfers are normal if you see how Real Madrid show they are bad to grow up their home-grown players. Many players grew their career better and became stars after they left Real Madrid. One of them is Samuel Eto'o. Real Madrid want super stars and handsome players in their squad.