"Another basis on which it is argued that greatly increased taxes on land are infeasible is that if land values were to fall precipitously, the financial system would collapse. It is true that many properties have mortgages that would exceed the value of the property if land taxes were increased significantly. This makes it necessary to think carefully about who should absorb the decline in aggregate asset value that would accompany a significant shift toward taxing land. Nevertheless, it is possible to plan for a restructured financial system that would have shed its dependence on land as collateral." http://www.wealthandwant.com/docs/Tideman_CTL.html#I._Taxing...
"Furthermore, as we discuss in more detail in our paper, the number of net winners from this reform would far exceed the number of net losers, who, if necessary, could be exempted or compensated at little budgetary cost. The winners would even include almost all of the very rich, who not only hold the vast majority of US land but who as a rule are also very well diversified, with land only accounting for a small share of their portfolios. They would benefit greatly from the countervailing cuts in labour and capital income taxes." https://voxeu.org/article/post-corona-balanced-budget-fiscal...
"It came as a quite natural development that also the question of incorporating these ideas into Danish Law was raised. From the very beginning, Jakob E. Lange was convinced that the problem of indebtedness, especially the mortgage debts, must be solved when the full Land Rent, or Ground Duty (in Danish "Grundskyld") were to be collected for a public revenue.
When in 1889 Henry George was on a speaking tour in England, Jakob E. Lange made use of the opportunity and went to England to meet him and to discuss the problem with him. The memoirs of Jakob E. Lange relate that Henry George completely accepted his standpoint; an eventual full Ground Rent which were to exceed the present property taxes ought to be proportioned between the title owner and the mortgage holder. This agreement between Henry George and Jacob E. Lange is also found expressed in the later correspondance between the two." https://cooperative-individualism.org/bille-frank_danish-ame...